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Rate allocation strategies for energy-efficient multipath routing in Ad-hoc networks towards B3G

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 84-88页

作者： ZHAN Song-tao XU Guo-xin Wireless Technologies Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Wireless mobile Ad-hoc network is a special network that all nodes can serf-organize and work together. It is flexible to form a network and extend the coverage area dynamically without infrastructure, so Ad-hoc network is envisioned as cornerstones of future generation networking technologies （B3G or 4（3）. However, the dynamic network topology makes the communication cost not only the energy of source/destination nodes, but also the relay nodes. Another problem of the Ad-hoc network is it is hard to provide a stable and persistent quality of service （QoS）, which is strongly required by the beyond 3rd generation （B3G） system. In this article, the authors establish a scenario that contains B3G cellular base station and Ad-hoc mobile nodes, and propose two algorithms minimum incremental rate algorithm and power feed-back rate allocation algorithm in multipath routing. The algorithms can maintain a constant total transmission rate and bit error ratio （BER） to provide the QoS guarantee and reach the minimum power consumption of the relay nodes by adjusting the rate of each path in the multipath routing.

关键词： Ad-hoc network B3G multipath routing energy consumption QoS

Rainfall Forecasting Using Machine Learning Algorithms for Localized Events

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Computers, Materials & Continua 2022年第6期71卷 6333-6350页

作者： Ganapathy Pattukandan Ganapathy Kathiravan Srinivasan Debajit Datta Chuan-Yu Chang Om Purohit Vladislav Zaalishvili Olga Burdzieva Centre for Disaster Mitigation and Management Vellore Institute of TechnologyVellore632014India School of Computer science and Engineering Vellore Institute of TechnologyVellore632014India Department of Computer science and Information Engineering National Yunlin University of Science and TechnologyYunlin64002Taiwan Service Systems technology Center Industrial Technology Research InstituteHsinchuTaiwan School of Information technology and Engineering Vellore Institute of TechnologyVellore632014India Geophysical Institute of Vladikavkaz Scientific Centre Russian Academy of Sciences(RAS)VladikavkazRussian Federation

A substantial amount of the Indian economy depends solely on ***,on the other hand,plays a significant role in agriculture–while an adequate amount of rainfall can be considered as a blessing,if the amount is inordinate or scant,it can ruin the entire hard work of the *** this work,the rainfall dataset of the Vellore region,of Tamil Nadu,India,in the years 2021 and 2022 is forecasted using several machine learning *** engineering has been performed in this work in order to generate new features that remove all sorts of autocorrelation present in the *** removal of autocorrelation,the data could be used for performing operations on the time-series data,which otherwise could only be performed on any other regular regression *** work uses forecasting techniques like the AutoRegessive Integrated Moving Average(ARIMA)and exponential smoothening,and then the time-series data is further worked on using Long Short Term Memory(LSTM).Later,regression techniques are used by manipulating the *** work is benchmarked with several evaluation metrics on a test dataset,where XGBoost Regression technique outperformed the *** uniqueness of this work is that it forecasts the daily rainfall for the year 2021 and 2022 in Vellore *** work can be extended in the future to predict rainfall over a bigger region based on previously recorded time-series data,which can help the farmers and common people to plan accordingly and take precautionary measures.

关键词： Time-series ARIMA LSTM regression rainfall

A comparison between artificial neural network algorithms and empirical equations applied to submerged weir scour evolution prediction

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International Journal of Sediment Research 2023年第1期38卷 105-114页

作者： Dawei Guan Jingang Liu Yee-Meng Chiew Jian-Hao Hong Liang Cheng Key Laboratory of ministry of Education for Coastal Disaster and Protection Hohai University School of Civil and Environment Engineering Nanyang Technological University Sustainability Center Nanhua University School of the Environment and Safety Engineering Jiangsu University

Estimating the time evolution of a local scour hole downstream of submerged weirs can help determine the maximum scour depth and length and is essential to designing submerged weir *** the current study, artificial neural networks with a backpropagation learning algorithm were used to estimate the temporal variation of scour profiles downstream of submerged weirs under clear water conditions. Physical factors, such as the flow condition, weir size, and sediment characteristics, are general scour considerations. Two sets of data combinations, namely original and non-dimensional data, were utilized in developing the backpropagation network(BPN) model. Using the data combinations and a trial-and-error method, the appropriate number of hidden neurons in the model architecture was determined. The results indicated that using non-dimensional variables as inputs in estimating the time evolution of scour holes downstream of a submerged weir is more suitable for the BPN model. Comparisons of the prediction results of the BPN model and an empirical regression formula revealed that the BPN model was more accurate and more direct in predicting the temporal variation of the local scour hole profile. In addition, sensitivity analysis showed that the dimensionless time exerted the most significant impact on the time evolution of the non-dimensional scour hole profile.

关键词： Submerged weir Scour profile Artificial neural networks (ANNs) Time evolution Backpropagation

Overview of priorities,threats,and challenges to biodiversity conservation in the southern Philippines

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Regional Sustainability 2023年第2期4卷 203-213页

作者： Angelo Rellama AGDUMA Francisco Gil GARCIA Ma.Teodora CABASAN Jonald PIMENTEL Renee Jane ELE Meriam RUBIO Sedra MURRAY Bona Abigail HILARIO-HUSAIN Kier Celestial Dela CRUZ Sumaira ABDULLAH Shiela Mae BALASE Krizler Cejuela TANALGO Ecology and Conservation Research Laboratory Department of Biological SciencesCollege of Science and MathematicsUniversity of Southern MindanaoCotabatoKabacan9407the Philippines Mindanao Open Biodiversity Information Project(MOBIOS+) c/o Ecology and Conservation Research LaboratoryDepartment of Biological SciencesCollege of Science and MathematicsUniversity of Southern MindanaoCotabatoKabacan9407the Philippines Department of Biological sciences College of Science and MathematicsUniversity of Southern MindanaoCotabatoKabacan9407the Philippines State Key Laboratory for Conservation and Utilization of Subtropical Agrobioresources Guangxi UniversityNanning530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning530004China Department of Agricultural Economics College of BusinessDevelopment Economics and ManagementUniversity of Southern MindanaoCotabatoKabacan 9407the Philippines Department of Mathematics and Statistics College of Science and MathematicsUniversity of Southern MindanaoCotabatoKabacan9407the Philippines Practical Genomics La boratory Department of BiologyCollege of ScienceDe La Salle University-ManilaManila1004the Philippines

Human activities have severely impacted on many species and ***,understanding the local biodiversity situation is crucial for implementing effective biodiversity conservation *** in the southern Philippines is home to various unique species,particularly in its pristine ***,the available biodiversity data for many terrestrial vertebrates and key areas remain *** address this issue,we synthesized published literature related to biodiversity from 2000 to 2022 in ***,this analysis used four key terrestrial vertebrates(amphibians,reptiles,birds,and mammals)in Mindanao as research *** to our findings,there was a significant and positive correlation between the number of biodiversity studies and species *** terms of species richness,birds were the most recorded group(n=334 spp.),followed by reptiles(n=108 spp.),mammals(n=70 spp.),and amphibians(n=52 spp.).We also found that the number of endemic and threatened species varies geographically and across taxonomic ***,we discovered a significant disparity in the information available on biodiversity in different provinces of *** example,the western provinces of Mindanao have had no record of biodiversity for more than two ***,we found that the changes in tree cover loss were consistent with biodiversity records,but this correlation is only significant for ***,we highlighted some critical threats and challenges to biodiversity,including deforestation,agricultural expansion,mining,and their impact on biodiversity conservation in *** findings suggested that biodiversity conservation should focus not only on areas with high levels of biodiversity but also on areas lacking biodiversity *** do this,we call for strengthening collaboration among various institutions and digitizing and centralizing of information related to *** gaining a deeper understanding of biodiversit

关键词： Biodiversity conservation Tree cover loss Mindanao Terrestrial vertebrates Endemic and threatened species

Threshold pressure gradient of fluid flow through multi-porous media in low and extra-low permeability reservoirs

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science China Earth sciences 2014年第8期57卷 2808-2818页

作者： DOU HongEn MA ShiYing ZOU CunYou YAO ShangLin Research Institute of Petroleum Exploration & Development PetroChina

After analyzing many studies of fluid flow theory of multi-porous media in low and extra-low permeability reservoirs and the numerical simulation of non-Darcy flow, we found that a negative flow rate occurs in the existing non-Darcy flow equation, which is unreasonable. We believe that the existing equation can only be considered as a discriminant to judging Darcy flow or non-Darcy flow, and cannot be taken as a fluid flow governing equation of multi-porous media. Our analysis of the experimental results shows that the threshold pressure gradient(TPG) of low and extra-low permeability reservoirs is excessively high, and does not conform to fluid flow through multi-porous media in the actual reservoir situation. Therefore, we present a reasonable TPG ranging from 0.006 to 0.04 MPa/m at the well depth of 1500 m and oil drainage distance of 500 m. The results of our study also indicate that the non-Darcy flow phenomenon will disappear when the TPG reaches a certain value. In addition, the TPG or non-Darcy flow in low and extra-low permeability reservoirs does not need to be considered in the productivity prediction and reservoir numerical simulation. At present, the black oil model or dual-porous media is suitable for simulating low and extra-low permeability reservoirs.

关键词：特低渗透油藏启动压力梯度流体流动多孔隙介质油藏数值模拟非达西渗流多孔介质模拟理论

A Fast Radio Burst Backend for the Tianlai Dish Pathfinder Array

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Research in Astronomy and Astrophysics 2022年第12期22卷 211-223页

作者： Zijie Yu Furen Deng Shijie Sun Chenhui Niu Jixia Li Fengquan Wu Wei-Yang Wang Yougang Wang Hui Feng Lin Shu Jie Hao Reza Ansari Albert Stebbins Xuelei Chen National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100049China Department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Institute of Automation Chinese Academy of SciencesBeijing 100190China Guangdong Institute of Artificial Intelligence and Advanced Computing Guangzhou 510535China UniversitéParis-Saclay CNRS/IN2P3IJCLabF-91405 OrsayFrance Fermi National Accelerator Laboratory P.O.Box 500BataviaIL 60510-5011United States of America Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Center of High Energy Physics Peking UniversityBeijing 100871China

The Tianlai Dish Pathfinder Array is a radio interferometer array consisting of 16 six-meter dish *** original digital backend integration time is at the seconds level,designed for H I intensity mapping experiment.A new digital backend with millisecond response is added to enable it to search for fast radio burst during its *** design and calibration of this backend,and the real time search pipeline for it are described in this *** is capable of forming 16 digital beams for each linear polarization,covering an area of 19.6 square *** search pipeline is capable of searching for,recording and classifying FRBs automatically in real *** commissioning,we succeeded in capturing the signal pulses from the pulsars PSR B0329+54 and B2021+51.

关键词： instrumentation:miscellaneous techniques:interferometric telescopes radio continuum:general (stars:)pulsars:general

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深化科技与金融结合赋能企业高质量创新

中国科学院院刊 2022年第9期37卷 1206-1215页

作者：薛薇胡贝贝魏世杰中国科学院科技战略咨询研究院北京100190 中国科学技术发展战略研究院北京100038

我国推动科技与金融结合已历经40余年,现已基本形成了覆盖企业技术创新不同环节的科技金融体系。当前我国已经进入高质量发展新阶段,面临新的发展形势,对科技金融提出重大挑战和突出问题,亟待进一步升级发展。面向新需求建议完善基于创... 详细信息

我国推动科技与金融结合已历经40余年,现已基本形成了覆盖企业技术创新不同环节的科技金融体系。当前我国已经进入高质量发展新阶段,面临新的发展形势,对科技金融提出重大挑战和突出问题,亟待进一步升级发展。面向新需求建议完善基于创新规律的融资体系,构建差异化定位、一体化链接的科技金融服务系统;大胆创新金融制度,探索建立全国政策性科技银行、在“新三板”建立终身保荐人制度等新举措;进一步明确政府创业投资基金的功能定位,培育“耐心”资本,引导社会资金“投科”“投小”“投早”“投长”;优化创新导向的政策环境,为科技与金融结合提供有力保障。

关键词：科技金融企业技术创新创新链

Mapping the resting cysts of dinoflagellate Alexandrium catenella along the coast of Qinhuangdao,China

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Journal of Oceanology and Limnology 2022年第6期40卷 2312-2321页

作者： Wenjiao TANG Huixia GENG Yanjuan XI Qingchun ZHANG Xuexi TANG Rencheng YU College of Marine Life science Ocean University of ChinaQingdao 266003China CAS Key Laboratory of Marine Ecology and Environmental sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Key Laboratory for Marine Ecology and Environmental science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of sciences Beijing 100049China Center for Ocean Mega-science Chinese Academy of SciencesQingdao 266071China Hebei Academy of Ocean and Fishery science Qinhuangdao 066200China

Dinoflagellate Alexandrium catenella is a cosmopolitan bloom-forming species with complex life cycle,the formation and germination of resting cysts are critical for its bloom *** the coastal waters of Qinhuangdao,*** has been identified as the major causative agent for paralytic shellfish poisoning,but there is little knowledge concerning its resting cysts in this *** this study,three surveys were carried out along the coast of Qinhuangdao from 2020 to 2021 to map the distribution of *** resting cysts,using a quantitative PCR(qPCR)assay specific for *** resting cysts were detected in surface sediments during all the three surveys,and their distribution patterns were *** abundance of resting cysts(maximum 1300 cysts/g sediment(wet weight))were found in a region(119.62°E-119.99°E,39.67°N-39.98°N)northeast to the coastal waters of Qinhuangdao,where surface sediments were mainly composed of clay and silt(percentage above 50%).Prior to the formation of the *** bloom in March 2021,the abundance of *** vegetative cells in seawater had extremely significant positive correlation with the abundance of resting cysts in surface sediments,reflecting the important role of resting cysts in the initiation of *** *** far as we know,this is the first report on the distribution of *** cysts along the coast of *** results will of fer a sound basis for the future monitoring and mitigation of toxic *** blooms and paralytic shellfish poisoning events in this region.

关键词： harmful algal bloom(HAB) Alexandrium catenella resting cyst paralytic shellfish toxin(PST) Qinhuangdao

A Layer-Based Mesh Generator and Scheme for 3D Printing Simulation

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Computer Modeling in Engineering & sciences 2019年第8期120卷 363-374页

作者： Ming-Hsiao Lee Shou-I Chen Wen-Hwa Chen Ying Mao National Center for High-performance Computing NARLHsinchu 30013Taiwan China University of technology TaipeiTaiwan National Tsing Hua University Hsinchu 30013Taiwan

3D Printing,also called Additive Manufacturing,has become a promising manufacturing method to produce parts in various fields as it can produce parts even with very irregular shapes in a relatively shorter process and ***,during the printing process,some problems could decrease the accuracy and quality of the printed parts,such as warpage due to thermal strains,deformation due to inadequate supports,*** finite element method is most commonly adopted to evaluate engineering problems in advance to reduce possible failures;however,the element meshes,needed for analyses,are always irregularly distributed,especially for irregular objects,and cannot match the layer-by-layer growing shapes of the printed parts in the 3D printing *** a proper element mesh,the analysis cannot be *** overcome this problem,a layer-based mesh generator combined with a corresponding scheme for the 3D Printing simulation is proposed and *** the proposed methods,the analysis models can be designed and generated to match the growing shapes,i.e.,layer-by-layer,and used to simulate the layer-by-layer growing behavior in the 3D printing ***,the proposed schemes directly adopt the Stereo-Lithography(STL)formatted geometric data as the geometry model on which the mesh generation and simulation are *** makes them even easier to use since the STL geometry format is a De facto standard format used in the 3D printing *** simulation cases have been conducted to demonstrate the effectiveness and efficiency of these proposed schemes.

关键词： 3D printing mesh generator layer-by-layer layer-based