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Intelligent identification and quantification method of rockburst behavior characteristics based on vision and 3D laser point cloud technology

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MEASUREMENT 2024年 237卷

作者： Zhang, Qinghe Wei, Chunxu Gao, Xiang Yuan, Liang Wang, Shengtao Shen, Zhijun Zhou, Jiawu Zhang, Xinsheng Anhui Univ Sci & Technol Sch Civil Engn & Architecture Huainan 232001 Peoples R China Anhui Univ Sci & Technol Joint Natl Local Engn Res Ctr Safe & Precise Coal Huainan 232001 Anhui Peoples R China Anhui Univ Sci & Technol State Key Lab Mine Response & Disaster Prevent & C Huainan 232001 Peoples R China China Railway 4 Engn Grp CO LTD Hefei 230022 Anhui Peoples R China

Aiming at the problem of recording rockburst events, a safe and intelligent identification technology and instrument are developed. The instrument mainly consists of a network spherical camera and LiDAR. Corresponding processing algorithms have been developed to automatically measure the occurrence time, location, velocity, and size of rockfalls during rockburst. The instrument was applied to a tunnel construction site in Southwest China, where 96 rockburst events were collected and identified. The results show that: rockburst in this tunnel mostly occur at the vault and right arch shoulder, mainly within 150 min after the tunnel face blasting, the velocity of the falling rocks can reach 12.297 m/s, the falling process is only about 1 s, and the size of the falling rocks is mainly stones smaller than 0.2 m3. The results indicate that this method has good detection performance and can provide beneficial technology and equipment for further statistical analysis of the occurrence patterns of rockburst.

关键词： Rockburst behavior characteristics Visual technology 3D LiDAR technology algorithm development Intelligent recognition

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Probabilistic global maps of crop-specific areas from 1961 to 2014

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ENVIRONMENTAL RESEARCH LETTERS 2019年第9期14卷 094023-094023页

作者： Jackson, Nicole D. Konar, Megan Debaere, Peter Estes, Lyndon Univ Illinois Dept Civil & Environm Engn Urbana IL 61801 USA Univ Virginia Darden Sch Business Charlottesville VA 22903 USA Clark Univ Grad Sch Geog Worcester MA 01610 USA

Agriculture has substantial socioeconomic and environmental impacts that vary between crops. However, information on how the spatial distribution of specific crops has changed over time across the globe is relatively sparse. We introduce the Probabilistic Cropland Allocation Model (PCAM), a novel algorithm to estimate where specific crops have likely been grown over time. Specifically, PCAM downscales annual and national-scale data on the crop-specific area harvested of 17 major crops to a global 0.5-degree grid from 1961 to 2014. To do this, pixels are assigned into probability clusters based upon crop-specific pixel suitability (based on mean climate and soil characteristics) and gridded historical agricultural areas. PCAM maps compare relatively well with an existing gridded dataset of crop-specific areas circa 2000 (simple matching coefficient value >0.8 for all crops). PCAM estimates compare less well with time series county-level agricultural census data for the United States. Importantly, deviations between census data and PCAM benchmark estimates (driven by soil and climate suitability) can be used to infer the importance of other factors of agricultural production (e.g. labor, agricultural policy, extreme climate) in future work. Our results provide new insights into the likely changes in the spatial distribution of major crops over the past half-century.

关键词： algorithm development global gridded probabilistic allocation crop suitability agricultural geography time series

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High-quality display for small-size Chinese characters by grid-fitting rules

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JOURNAL OF ELECTRONIC IMAGING 2007年第3期16卷 033002.1-033002.11页

作者： Chen, Thou-Ho Wang, Da-Jinn Chen, Tsong-Yi Natl Kaohsiung Univ Appl Sci Dept Elect Engn Kaohsiung 807 Taiwan

A grid-fitting method for Chinese fonts at a size smaller than 20 grid units to achieve a high-quality display is presented. The basic idea behind the proposed method is to adopt several grid-fitting rules with a gray-scaling strategy. The major procedures include supersampling, adjusting the position and width of strokes, gray-scale filtering, and subsampling. The experimental results show that the jagged edge induced by the coarse resolution can be removed and that the rendition of character details and the contrast are also improved, revealing that the character's clarity and smoothness can be enhanced for a higher legibility with comfortable reading. (c) 2007 SPIE and IS&T.

关键词： Gaussian filters Visualization Information visualization Data processing Roads algorithm development Applied sciences Electronics engineering Linear filtering Optical resolution

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Remote sensing of air pollutants in China to study the effects of emission reduction policies on air quality

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JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS 2024年 265卷

作者： de Leeuw, Gerrit van der Ronald, A. Bai, Jianhui den Hoed, Mirjam Ding, Jieying Guo, Jianping Li, Zhengqiang Zhang, Ying Fan, Cheng Qin, Kai Sinnathamby, Selviga Safieddine, Sarah Varotsos, Costas Xue, Yong Yin, Yan Zhang, Qianqian Zhang, Xin Zhang, Xingying Zhang, Xiumei Royal Netherlands Meteorol Inst KNMI R&D Satellite Observat NL-3731 GA De Bilt Netherlands Chinese Acad Sci AirCAS Aerosp Informat Res Inst 20 Datun Rd Beijing 100101 Peoples R China Nanjing Univ Informat Sci & Technol NUIST KNMI NUIST Ctr Atmospher Composit Nanjing 210044 Peoples R China Chinese Acad Sci IAP CAS Inst Atmospher Phys LAGEO Beijing 100029 Peoples R China Chinese Acad Meteorol Sci State Key Lab Severe Weather Beijing Peoples R China China Univ Min & Technol CUMT Sch Environm Sci & Spatial Informat Xuzhou 221116 Jiangsu Peoples R China Sorbonne Univ CNRS LATMOS IPSL UVSQ Paris France Natl & Kapodistrian Univ Athens Dept Environm Phys & Meteorol Univ CampusBldg PHYS V GR-15784 Athens Greece Univ Derby Sch Comp & Math Kedleston Rd Derby DE22 1GB England China Meteorol Adm Natl Satellite Meteorol Ctr Beijing 100081 Peoples R China Nanjing Univ Informat Sci & Technol NUIST Key Lab Aerosol Cloud Precipitat China Meteorol Adm Nanjing 210044 Peoples R China China Meteorol Adm Dept Sci & Technol & Climate Change Beijing 100081 Peoples R China

Air Quality (AQ) is determined by the concentrations of aerosols and trace gases. Aerosol concentration is measured by the mass concentration of particles smaller than 2.5 mu m (PM2.5) or 10 mu m (PM10), while trace gases include ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO). Ammonia (NH3) and (biogenic) volatile organic compounds ((B)VOCs) also play an important role in atmospheric chemistry affecting the concentrations of trace gases and ultimately AQ. This study focuses on various aspects of AQ in China, utilizing remote sensing data from satellite and ground-based sensors to obtain information on PM emissions and concentrations and AQ-relevant trace gases. This research was conducted within the framework of the ESA/NRSCC MOST collaboration project Dragon 5, as part of the EMPAC (Exploitation of satellite remote sensing to enhance our comprehension of the Mechanisms and Processes influencing Air quality in China) project. It summarizes findings on four main topics: (1) Retrieval of trace gas concentrations and aerosol products from satellite data, validation using ground-based reference data, and interpretation of results in terms of AQ effects, such as the conversion of column-integrated properties to near-surface concentrations;(2) Determination of trace gases emissions relevant to AQ, using satellite data and models;(3) Analysis of time series data on trace gases and aerosols to assess the impact of emission reduction policies on AQ improvement;(4) Research contributing to a deeper understanding of mechanisms and processes affecting atmospheric composition about AQ.

关键词： Earth observation algorithm development Validation Atmosphere Air quality Emissions Aerosols Trace gases Atmospheric processes Trends

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Volume estimates of trees with complex architecture from terrestrial laser scanning

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JOURNAL OF APPLIED REMOTE SENSING 2008年第1期2卷 023521-023521页

作者： Lefsky, Michael McHale, Melissa Colorado State Univ Dept Nat Resources Ctr Ecol Anal Lidar Ft Collins CO 80523 USA Arizona State Univ Global Inst Sustainabil Tempe AZ 85287 USA

Research on urban forest carbon storage requires new allometric equations that relate easily measured aspects of tree form to total tree volume. Existing methods for creating these equations are time consuming and can require destructive sampling. In this study we used a terrestrial lidar sensor;data produced by this system consists of the three-dimensional locations of points that lay on object surfaces (in this case the trunk, branches, twigs, etc.). The challenge in calculating tree volume was the aggregation of these individual points into objects whose dimensions could be reliably estimated. We converted the lidar observations into 3-dimensional voxels, identified narrow (< 20 cm) sections along the stems, and merged sections on the basis of their connectivity. The distribution of returns from small branches was analyzed on the basis of branch size and the sampling pattern of the sensor. Two hundred and fifty measurements of stem diameter were made on 14 trees of two species using both lidar and field measurements;the estimates were highly correlated (r(2) > 98%) and unbiased. The processing algorithm was applied to lidar data from 179 trees of 11 species;the accuracy of results was dependant on tree volume, species and tree form.

关键词： terrestrial lidar urban trees allometric relationships volume equations algorithm development

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Special Section Guest Editorial: Advances in Computational Methods for Optical System Forward- and Inverse-Design

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OPTICAL ENGINEERING 2023年第2期62卷 021001-021001页

作者： Campbell, Sawyer D. Jungwirth, Matthew E. L. Penn State Univ Sch Elect Engn & Comp Sci University Pk PA 16801 USA CyberOpt Corp Minneapolis MN USA

. Special section editors Sawyer D. Campbell and Matthew E.L. Jungwirth introduce the Special Section on Advances in Computational Methods for Optical System Forward- and Inverse-Design.

关键词： Deep learning Design and modelling Evolutionary algorithms Optical engineering Visible light communication algorithm development Artificial intelligence Optical design Phase modulation Visualization

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An algorithm to predict the connectome of neural microcircuits

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FRONTIERS IN COMPUTATIONAL NEUROSCIENCE 2015年第OCT期9卷 120页

作者： Reimann, Michael W. King, James G. Muller, Eilif B. Ramaswamy, Srikanth Markram, Henry Ecole Polytech Fed Lausanne Blue Brain Project CH-1202 Geneva Switzerland

Experimentally mapping synaptic connections, in terms of the numbers and locations of their synapses and estimating connection probabilities, is still not a tractable task, even for small volumes of tissue. In fact, the six layers of the neocortex contain thousands of unique types of synaptic connections between the many different types of neurons, of which only a handful have been characterized experimentally. Here we present a theoretical framework and a data-driven algorithmic strategy to digitally reconstruct the complete synaptic connectivity between the different types of neurons in a small well-defined volume of tissue the micro scale connectome of a neural microcircuit. By enforcing a set of established principles of synaptic connectivity, and leveraging interdependencies between fundamental properties of neural microcircuits to constrain the reconstructed connectivity, the algorithm yields three parameters per connection type that predict the anatomy of all types of biologically viable synaptic connections. The predictions reproduce a spectrum of experimental data on synaptic connectivity not used by the algorithm. We conclude that an algorithmic approach to the connectome can serve as a tool to accelerate experimental mapping, indicating the minimal dataset required to make useful predictions, identifying the datasets required to improve their accuracy, testing the feasibility of experimental measurements, and making it possible to test hypotheses of synaptic connectivity.

关键词： neocortex algorithm development connectome mapping synaptic transmission in silico somatosensory cortex cortical circuits

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Wearable chest sensor for stride and respiration detection during running

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SPORTS ENGINEERING 2023年第1期26卷 19-19页

作者： Bernhart, Severin Harbour, Eric Kranzinger, Stefan Jensen, Ulf Finkenzeller, Thomas Salzburg Res Forsch Gesell MbH Jakob Haringer Str 5 A-5020 Salzburg Austria Salzburg Univ Dept Sport & Exercise Sci Schlossallee 49 A-5400 Hallein Rif Austria Adidas AG Adi Dassler Str 1 D-91074 Herzogenaurach Germany

Endurance running is among the most popular physical activities partially due to its low barriers to entry. However, some people avoid running because of respiratory distress, and respiratory monitoring could help prevent this. Wearable sensors are valuable for respiration detection during exercise and enable respiratory feedback in real time. Therefore, this study presents a wearable chest-mounted stride and respiration sensor including step and flow reversal event detection algorithms. The algorithms were evaluated using precision and recall between detected and reference events with respect to different levels of breathing depth, motion artifact, thoracic skin temperature and sweat. Overall F1 scores reached 93.2%, 97.4% and 97.2% for step, expiration and inspiration events, respectively. No significant effect on event detection performance was observed for breathing depth, stride motion artifact, or thoracic skin temperature. In contrast, sweat level slightly decreased detection performance. Consequently, this sensor is able to accurately measure stride and respiration during running and could be suitable for use as a system to guide runners' respiration during exercise.

关键词： algorithm development Respiration Textile sensors Wearable

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A method for monitoring reactive strength index

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Procedia Engineering 2010年第2期2卷 3115-3120页

作者： Matt Patterson Brian Caulfield Clarity Centre for Sensor Web Technologies University College Dublin Belfield Dublin 4 Ireland

Ubiquitous motion sensors in shoes and clothing are becoming more prevalent. This new data stream opens a large opportunity to gain a deeper understanding of human movement. This paper describes the development and validation of an algorithm to calculate reactive strength index (RSI) from an accelerometer mounted at the ankle. Compared to the gold standard force-plate, the accelerometer and algorithm RSI had r = 0.98 , mean difference=0.001 m/sec and a confidence interval ranging from 0.12 to −0.11 m/sec. Difficulty in accurately identifying take-off using the accelerometer was the main source of measurement error.

关键词： Accelerometer Feature extraction algorithm development Reactive strength index Validation Force plate Athletic performance

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Special section guest editorial: Computational approaches to imaging LADAR

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Optical Engineering 2015年第3期54卷

作者： Rabb, David Marron, Joseph Air Force Research Laboratory Wright Patterson AFB OH United States Raytheon Space and Airborne Systems El SegundoCA United States

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