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Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China
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作者 Jingya Zhang Cui Xiao +5 位作者 Xiaoyu Duan Xin Gao Hao Zeng Rong'an Dong Gang Feng Keping Ma 《Plant Diversity》 SCIE CAS CSCD 2024年第3期353-361,共9页
Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection... Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate. 展开更多
关键词 Biological specimen collection preference Dominant plant species Environmental range Geographical range Species traits
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Flight Time Minimization of UAV for Cooperative Data Collection in Probabilistic LoS Channel
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作者 Yan Li Shaoyi Xu +1 位作者 Yunpu Wu Dongji Li 《China Communications》 SCIE CSCD 2024年第2期210-226,共17页
This paper investigates the data collection in an unmanned aerial vehicle(UAV)-aided Internet of Things(IoT) network, where a UAV is dispatched to collect data from ground sensors in a practical and accurate probabili... This paper investigates the data collection in an unmanned aerial vehicle(UAV)-aided Internet of Things(IoT) network, where a UAV is dispatched to collect data from ground sensors in a practical and accurate probabilistic line-of-sight(LoS) channel. Especially, access points(APs) are introduced to collect data from some sensors in the unlicensed band to improve data collection efficiency. We formulate a mixed-integer non-convex optimization problem to minimize the UAV flight time by jointly designing the UAV 3D trajectory and sensors’ scheduling, while ensuring the required amount of data can be collected under the limited UAV energy. To solve this nonconvex problem, we recast the objective problem into a tractable form. Then, the problem is further divided into several sub-problems to solve iteratively, and the successive convex approximation(SCA) scheme is applied to solve each non-convex subproblem. Finally,the bisection search is adopted to speed up the searching for the minimum UAV flight time. Simulation results verify that the UAV flight time can be shortened by the proposed method effectively. 展开更多
关键词 data collection flight time probabilistic line-of-sight channel unlicensed band unmanned aerial vehicle
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Actor-Critic-Based UAV-Assisted Data Collection in the Wireless Sensor Network
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作者 Huang Xiaoge Wang Lingzhi +1 位作者 He Yong Chen Qianbin 《China Communications》 SCIE CSCD 2024年第4期163-177,共15页
Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible installation.However,WSN data collection encounters challenges in scenarios lacki... Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible installation.However,WSN data collection encounters challenges in scenarios lacking communication infrastructure.Unmanned aerial vehicle(UAV)offers a novel solution for WSN data collection,leveraging their high mobility.In this paper,we present an efficient UAV-assisted data collection algorithm aimed at minimizing the overall power consumption of the WSN.Firstly,a two-layer UAV-assisted data collection model is introduced,including the ground and aerial layers.The ground layer senses the environmental data by the cluster members(CMs),and the CMs transmit the data to the cluster heads(CHs),which forward the collected data to the UAVs.The aerial network layer consists of multiple UAVs that collect,store,and forward data from the CHs to the data center for analysis.Secondly,an improved clustering algorithm based on K-Means++is proposed to optimize the number and locations of CHs.Moreover,an Actor-Critic based algorithm is introduced to optimize the UAV deployment and the association with CHs.Finally,simulation results verify the effectiveness of the proposed algorithms. 展开更多
关键词 actor critic data collection deep reinforcement learning unmanned aerial vehicle wireless sensor network
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Endoscopic intramural cystogastrostomy for treatment of peripancreatic fluid collection: A viewpoint from a surgeon
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作者 Chen-Guo Ker 《World Journal of Gastroenterology》 SCIE CAS 2024年第6期610-613,共4页
Percutaneous or endoscopic drainage is the initial choice for the treatment of peripancreatic fluid collection in symptomatic patients.Endoscopic transgastric fenestration(ETGF)was first reported for the management of... Percutaneous or endoscopic drainage is the initial choice for the treatment of peripancreatic fluid collection in symptomatic patients.Endoscopic transgastric fenestration(ETGF)was first reported for the management of pancreatic pseu-docysts of 20 patients in 2008.From a surgeon’s viewpoint,ETGF is a similar procedure to cystogastrostomy in that they both produce a wide outlet orifice for the drainage of fluid and necrotic debris.ETGF can be performed at least 4 wk after the initial onset of acute pancreatitis and it has a high priority over the surgical approach.However,the surgical approach usually has a better success rate because surgical cystogastrostomy has a wider outlet(>6 cm vs 2 cm)than ETGF.However,percutaneous or endoscopic drainage,ETGF,and surgical approach offer various treatment options for peripancreatic fluid collection patients based on their conditions. 展开更多
关键词 Pancreatitis Pancreatic pseudocyst Endoscopic cystogastrostomy Surgical cystogastrostomy Peripancreatic fluid collection Fenestration for pancreatic cyst
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Customized Convolutional Neural Network for Accurate Detection of Deep Fake Images in Video Collections
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作者 Dmitry Gura Bo Dong +1 位作者 Duaa Mehiar Nidal Al Said 《Computers, Materials & Continua》 SCIE EI 2024年第5期1995-2014,共20页
The motivation for this study is that the quality of deep fakes is constantly improving,which leads to the need to develop new methods for their detection.The proposed Customized Convolutional Neural Network method in... The motivation for this study is that the quality of deep fakes is constantly improving,which leads to the need to develop new methods for their detection.The proposed Customized Convolutional Neural Network method involves extracting structured data from video frames using facial landmark detection,which is then used as input to the CNN.The customized Convolutional Neural Network method is the date augmented-based CNN model to generate‘fake data’or‘fake images’.This study was carried out using Python and its libraries.We used 242 films from the dataset gathered by the Deep Fake Detection Challenge,of which 199 were made up and the remaining 53 were real.Ten seconds were allotted for each video.There were 318 videos used in all,199 of which were fake and 119 of which were real.Our proposedmethod achieved a testing accuracy of 91.47%,loss of 0.342,and AUC score of 0.92,outperforming two alternative approaches,CNN and MLP-CNN.Furthermore,our method succeeded in greater accuracy than contemporary models such as XceptionNet,Meso-4,EfficientNet-BO,MesoInception-4,VGG-16,and DST-Net.The novelty of this investigation is the development of a new Convolutional Neural Network(CNN)learning model that can accurately detect deep fake face photos. 展开更多
关键词 Deep fake detection video analysis convolutional neural network machine learning video dataset collection facial landmark prediction accuracy models
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Early endoscopic management of an infected acute necrotic collection misdiagnosed as a pancreatic pseudocyst: A case report
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作者 Hong-Ying Zhang Chen-Cong He 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期609-615,共7页
BACKGROUND Infected acute necrotic collection(ANC)is a fatal complication of acute pancre-atitis with substantial morbidity and mortality.Drainage plays an exceedingly important role as the first step in invasive inte... BACKGROUND Infected acute necrotic collection(ANC)is a fatal complication of acute pancre-atitis with substantial morbidity and mortality.Drainage plays an exceedingly important role as the first step in invasive intervention for infected necrosis;however,there is great controversy about the optimal drainage time,and better treatment should be explored.CASE SUMMARY We report the case of a 43-year-old man who was admitted to the hospital with severe intake reduction due to early satiety 2 wk after treatment for acute pancre-atitis;conservative treatment was ineffective,and a pancreatic pseudocyst was suspected on contrast-enhanced computed tomography(CT).Endoscopic ultra-sonography(EUS)suggested hyperechoic necrotic tissue within the cyst cavity.The wall was not completely mature,and the culture of the puncture fluid was positive for A-haemolytic Streptococcus.Thus,the final diagnosis of ANC in-fection was made.The necrotic collection was not walled off and contained many solid components;therefore,the patient underwent EUS-guided aspiration and lavage.Two weeks after the collection was completely encapsulated,pancreatic duct stent drainage via endoscopic retrograde cholangiopancreatography(ERCP)was performed,and the patient was subsequently successfully discharged.On repeat CT,the pancreatic cysts had almost disappeared during the 6-month fo-llow-up period after surgery.CONCLUSION Early EUS-guided aspiration and lavage combined with late ERCP catheter drainage may be effective methods for intervention in infected ANCs. 展开更多
关键词 Infected acute necrotic collection Pancreatic pseudocyst Endoscopic ultrasonography Endoscopic retrograde cholangiopancreatography Endoscopic ultrasound-guided fine-needle aspiration Case report
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Exploring Corporate Tax Compliance in the Era of Digital Tax Collection and Administration:Insights from the“Golden Tax Phase Four”Project
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作者 Kai Fan Yujin Xie +1 位作者 Wenjun Xu Haopeng Wei 《Proceedings of Business and Economic Studies》 2024年第2期151-156,共6页
This article primarily examines the current state of tax collection and management,alongside other associated issues.It integrates insights from China’s“14th Five-Year Plan”and anticipates the imminent implementati... This article primarily examines the current state of tax collection and management,alongside other associated issues.It integrates insights from China’s“14th Five-Year Plan”and anticipates the imminent implementation of the“Golden Tax Phase Four.”With this backdrop,the article offers recommendations for advancing the reform of the tax collection and management system,fostering the development of intelligent taxation,and accelerating the modernization of tax collection and management in China. 展开更多
关键词 Golden Tax Phase Four Modernization of tax collection and administration Tax compliance
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Endoscopic transgastric fenestration versus percutaneous drainage for management of(peri)pancreatic fluid collections adjacent to gastric wall(with video) 被引量:1
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作者 Hong-Mei Zhang Hui-Ting Ke +7 位作者 Md Robin Ahmed Ya-Juan Li Ghulam Nabi Mu-Han Li Ji-Yu Zhang Dan Liu Li-Xia Zhao Bing-Rong Liu 《World Journal of Gastroenterology》 SCIE CAS 2023年第40期5557-5565,共9页
BACKGROUND Percutaneous drainage(PCD)and endoscopic approaches have largely replaced surgical drainage as the initial approach for(peri)pancreatic fluid collections(PFC)s,while complications associated with endoscopic... BACKGROUND Percutaneous drainage(PCD)and endoscopic approaches have largely replaced surgical drainage as the initial approach for(peri)pancreatic fluid collections(PFC)s,while complications associated with endoscopic stent implantation are common.AIM To introduce a novel endoscopic therapy named endoscopic transgastric fenestration(ETGF),which involves resection of tissue by endoscopic accessory between gastric and PFCs without stent implantation,and to evaluate its efficacy and safety compared with PCD for the management of PFCs adjacent to the gastric wall.METHODS Patients diagnosed with PFCs adjacent to the gastric wall and who subsequently received ETGF or PCD were restrospectively enrolled.Indications for intervention were consistent with related guidelines.We analyzed patients baseline characteristics,technical and clinical success rate,recurrence and reintervention rate,procedure-related complications and adverse events.RESULTS Seventy-two eligible patients were retrospectively identified(ETGF=34,PCD=38)from October 2017 to May 2021.Patients in the ETGF group had a significantly higher clinical success rate than those in the PCD group(97.1 vs 76.3%,P=0.01).There were no statistically significant differences regarding recurrence,reintervention and incidence of complication between the two groups.While long-term catheter drainage was very common in the PCD group.CONCLUSION Compared with PCD,ETGF has a higher clinical success rate in the management of PFCs adjacent to the gastric wall.ETGF is an alternative effective strategy for the treatment of PFCs adjacent to the gastric wall. 展开更多
关键词 (Peri)Pancreatic fluid collections Endoscopic transgastric fenestration Percutaneous drainage
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Optimal Design of Aperture Illuminations for Microwave Power Transmission with Annular Collection Areas
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作者 Xun Li Baoyan Duan +1 位作者 Yiqun Zhang Yongxin Guo 《Engineering》 SCIE EI CAS CSCD 2023年第11期63-74,共12页
This work presents an optimal design method of antenna aperture illumination for microwave power transmission with an annular collection area.The objective is to maximize the ratio of the power radiated on the annular... This work presents an optimal design method of antenna aperture illumination for microwave power transmission with an annular collection area.The objective is to maximize the ratio of the power radiated on the annular collection area to the total transmitted power.By formulating the aperture amplitude distribution through a summation of a special set of series,the optimal design problem can be reduced to finding the maximum ratio of two real quadratic forms.Based on the theory of matrices,the solution to the formulated optimization problem is to determine the largest characteristic value and its associated characteristic vector.To meet security requirements,the peak radiation levels outside the receiving area are considered to be extra constraints.A hybrid grey wolf optimizer and Nelder–Mead simplex method is developed to deal with this constrained optimization problem.In order to demonstrate the effectiveness of the proposed method,numerical experiments on continuous apertures are conducted;then,discrete arrays of isotropic elements are employed to validate the correctness of the optimized results.Finally,patch arrays are adopted to further verify the validity of the proposed method. 展开更多
关键词 Microwave power transmission Beam collection efficiency Ring-shaped beam Annular collection area Grey wolf optimizer Nelder-Mead simplex method
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Core collection construction of tea plant germplasm in Anhui Province based on genetic diversity analysis using simple sequence repeat markers
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作者 TAO Ling-ling TING Yu-jie +7 位作者 CHEN Hong-rong WEN Hui-lin XIE Hui LUO Ling-yao HUANG Ke-lin ZHU Jun-yan LIU Sheng-rui WEI Chao-ling 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第9期2719-2728,共10页
The tea plant[Camellia sinensis(L.)O.Kuntze]is an industrial crop in China.The Anhui Province has a long history of tea cultivation and has a large resource of tea germplasm with abundant genetic diversity.To reduce t... The tea plant[Camellia sinensis(L.)O.Kuntze]is an industrial crop in China.The Anhui Province has a long history of tea cultivation and has a large resource of tea germplasm with abundant genetic diversity.To reduce the cost of conservation and utilization of germplasm resources,a core collection needs to be constructed.To this end,573 representative tea accessions were collected from six major tea-producing areas in Anhui Province.Based on 60 pairs of simple sequence repeat(SSR)markers,phylogenetic relationships,population structure and principal coordinate analysis(PCoA)were conducted.Phylogenetic analysis indicated that the 573 tea individuals clustered into five groups were related to geographical location and were consistent with the results of the PCoA.Finally,we constructed a core collection consisting of 115 tea individuals,accounting for 20%of the whole collection.The 115 core collections were considered to have a 90.9%retention rate for the observed number of alleles(Na),and Shannon’s information index(I)of the core and whole collections were highly consistent.Of these,39 individuals were preserved in the Huangshan area,accounting for 33.9%of the core collection,while only 10 individuals were reserved in the Jinzhai County,accounting for 8.9%of the core set.PCoA of the accessions in the tea plant core collection exhibited a pattern nearly identical to that of the accessions in the entire collection,further supporting the broad representation of the core germplasm in Anhui Province.The results demonstrated that the core collection could represent the genetic diversity of the original collection.Our present work is valuable for the high-efficiency conservation and utilization of tea plant germplasms in Anhui Province. 展开更多
关键词 tea plant core collection genetic diversity SSR markers
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AUV-Aided Data Collection Considering Adaptive Ocean Currents for Underwater Wireless Sensor Networks
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作者 Yunyun Li Yanjing Sun +1 位作者 Qingyan Ren Song Li 《China Communications》 SCIE CSCD 2023年第4期356-367,共12页
Autonomous underwater vehicle(AUV)-assisted data collection is an efficient approach to implementing smart ocean.However,the data collection in time-varying ocean currents is plagued by two critical issues:AUV yaw and... Autonomous underwater vehicle(AUV)-assisted data collection is an efficient approach to implementing smart ocean.However,the data collection in time-varying ocean currents is plagued by two critical issues:AUV yaw and sensor node movement.We propose an adaptive AUV-assisted data collection strategy for ocean currents to address these issues.First,we consider the energy consumption of an AUV in conjunction with the value of information(VoI)over the sensor nodes and formulate an optimization problem to maximize the VoI-energy ratio.The AUV yaw problem is then solved by deriving the AUV's reachable region in different ocean current environments and the optimal cruising direction to the target nodes.Finally,using the predicted VoI-energy ratio,we sequentially design a distributed path planning algorithm to select the next target node for AUV.The simulation results indicate that the proposed strategy can utilize ocean currents to aid AUV navigation,thereby reducing the AUV's energy consumption and ensuring timely data collection. 展开更多
关键词 underwater sensor networks data collection ocean currents value of information energy consumption
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Real-Time Data Transmission with Data Carrier Support Value in Neighbor Strategic Collection in WSN
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作者 S.Ponnarasi T.Rajendran 《Computers, Materials & Continua》 SCIE EI 2023年第6期6039-6057,共19页
An efficient trust-aware secure routing and network strategy-based data collection scheme is presented in this paper to enhance the performance and security of wireless sensor networks during data collection.The metho... An efficient trust-aware secure routing and network strategy-based data collection scheme is presented in this paper to enhance the performance and security of wireless sensor networks during data collection.The method first discovers the routes between the data sensors and the sink node.Several factors are considered for each sensor node along the route,including energy,number of neighbours,previous transmissions,and energy depletion ratio.Considering all these variables,the Sink Reachable Support Measure and the Secure Communication Support Measure,the method evaluates two distinct measures.The method calculates the data carrier support value using these two metrics.A single route is chosen to collect data based on the value of data carrier support.It has contributed to the design of Secure Communication Support(SCS)Estimation.This has been measured according to the strategy of each hop of the route.The suggested method improves the security and efficacy of data collection in wireless sensor networks.The second stage uses the two-fish approach to build a trust model for secure data transfer.A sim-ulation exercise was conducted to evaluate the effectiveness of the suggested framework.Metrics,including PDR,end-to-end latency,and average residual energy,were assessed for the proposed model.The efficiency of the suggested route design serves as evidence for the average residual energy for the proposed framework. 展开更多
关键词 Data carrier support data collection neighbor strategy secure routing wireless sensor network
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NOMA Empowered Energy Efficient Data Collection and Wireless Power Transfer in Space-Air-Ground Integrated Networks
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作者 Cong Zhou Shuo Shi +1 位作者 Chenyu Wu Zhenyu Xu 《China Communications》 SCIE CSCD 2023年第8期17-31,共15页
As the sixth generation network(6G)emerges,the Internet of remote things(IoRT)has become a critical issue.However,conventional terrestrial networks cannot meet the delay-sensitive data collection needs of IoRT network... As the sixth generation network(6G)emerges,the Internet of remote things(IoRT)has become a critical issue.However,conventional terrestrial networks cannot meet the delay-sensitive data collection needs of IoRT networks,and the Space-Air-Ground integrated network(SAGIN)holds promise.We propose a novel setup that integrates non-orthogonal multiple access(NOMA)and wireless power transfer(WPT)to collect latency-sensitive data from IoRT networks.To extend the lifetime of devices,we aim to minimize the maximum energy consumption among all IoRT devices.Due to the coupling between variables,the resulting problem is non-convex.We first decouple the variables and split the original problem into four subproblems.Then,we propose an iterative algorithm to solve the corresponding subproblems based on successive convex approximation(SCA)techniques and slack variables.Finally,simulation results show that the NOMA strategy has a tremendous advantage over the OMA scheme in terms of network lifetime and energy efficiency,providing valuable insights. 展开更多
关键词 NOMA Space-Air-Ground Integrated Networks data collection wireless power transfer resource allocation trajectory optimization
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Energy-Efficient Data Collection over Underwater MI-Assisted Acoustic Cooperative MIMO WSNs
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作者 Qingyan Ren Yanjing Sun +2 位作者 Song Li Bin Wang Zhengda Yu 《China Communications》 SCIE CSCD 2023年第11期96-110,共15页
Underwater magnetic induction(MI)-assisted acoustic cooperative multiple-input-multipleoutput(MIMO) has been recently proposed as a promising technique for underwater wireless sensor networks(UWSNs).For the more,the e... Underwater magnetic induction(MI)-assisted acoustic cooperative multiple-input-multipleoutput(MIMO) has been recently proposed as a promising technique for underwater wireless sensor networks(UWSNs).For the more,the energy utilization of energy-constrained sensor nodes is one of the key issues in UWSNs,and it relates to the network lifetime.In this paper,we present an energy-efficient data collection for underwater MI-assisted acoustic cooperative MIMO wireless sensor networks(WSNs),including the formation of cooperative MIMO and relay link establishment.Firstly,the cooperative MIMO is formed by considering its expected transmission range and the energy balance of nodes with it.Particularly,from the perspective of the node’s energy consumption,the expected cooperative MIMO size and the selection of master node(MN) are proposed.Sequentially,to improve the coverage of the networks and prolong the network lifetime,relay links are established by relay selection algorithm that using matching theory.Finally,the simulation results show that the proposed data collection improves its efficiency,reduces the energy consumption of the master node,improves the networks’ coverage,and extends the network lifetime. 展开更多
关键词 cooperative MIMO cooperative MIMO size data collection heterogeneous UWSNs relay link establishment
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Discussion on Collection of Precious Meteorological Archives under the Background of New Archives Law
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作者 Xiaobei LIU Xiao LIU +1 位作者 Yun CAI Song YUAN 《Meteorological and Environmental Research》 CAS 2023年第3期45-47,53,共4页
On January 1,2021,the newly revised Archives Law of the People's Republic of China(hereinafter referred to as the new Archives Law)was officially implemented,providing legal protection for archive management,archi... On January 1,2021,the newly revised Archives Law of the People's Republic of China(hereinafter referred to as the new Archives Law)was officially implemented,providing legal protection for archive management,archive work and archive undertaking in the new era.Starting from the relevant provisions of the new Archives Law,the collection of precious meteorological archives was discussed,and it is believed that only on the basis of clarifying the definition,collection responsibility subject,collection scope,ways and methods of precious meteorological archives can the relevant units be convenient to practice and obtain substantive collection effect. 展开更多
关键词 Archives Law Precious meteorological archives collection IDENTIFICATION
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Study on Rural Solid Waste Collection and Transportation Mode and Route Optimization Strategy in the Cold Regions of Northern China
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作者 Li Chuan-gang Liu Peng +1 位作者 Xu Hui Ma Li 《Journal of Northeast Agricultural University(English Edition)》 2023年第4期75-88,共14页
Rural vitalization is a major strategy for reform and development of agriculture and rural areas in China,the key task of which is improving rural living environment.Imperfect rural solid waste(RSW)collection and tran... Rural vitalization is a major strategy for reform and development of agriculture and rural areas in China,the key task of which is improving rural living environment.Imperfect rural solid waste(RSW)collection and transportation system exacerbates the pollution of RSW to rural living environment,while it has not been established and improved in the cold region of Northern China due to climate and economy.Through the analysis of the current situation of RSW source separation,collection,transportation and disposal in China,an RSW collection and transportation system suitable for the northern cold region was developed.Considering the low winter temperature in the northern cold region,different requirements for RSW collection,transportation and terminal disposal,scattered source points and single terminal disposal nodes in rural areas,the study focused on determining the number and location of transfer stations,established a model for transfer stations selection and RSW collection and transportation routes optimization for RSW collection and transportation system,and proposed the elite retention particle swarm optimization–genetic algorithm(ERPSO–GA).The rural area of Baiquan County was taken as a representative case,the collection and transportation scheme of which was given,and the feasibility of the scheme was clarified by simulation experiment. 展开更多
关键词 rural solid waste(RSW) collection and transportation route optimization rural environment collection and transportation costs elite retention particle swarm optimization-genetic algorithm(ERPSO-GA)
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Design and implementation of railway green performance basic data collection system
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作者 Xiangru Lyu Hui Li 《High-Speed Railway》 2023年第4期265-272,共8页
This study addressed the issues related to the collection and management of basic data for railway green performance. A railway green performance basic database has been constructed based on metadata and data exchange... This study addressed the issues related to the collection and management of basic data for railway green performance. A railway green performance basic database has been constructed based on metadata and data exchange schemas. A data classification system has been established from the perspectives of businesses, processes,and entities. A BIM(Building Information Modelling) model data extraction scheme is proposed based on field similarity matching and a document content extraction scheme is proposed based on image recognition. A railway green performance basic data collection system has been developed, achieving efficient collection and integrated management of railway green performance basic data. This system can provide data support for applications such as railway carbon emissions accounting, green cost-benefit analysis, and evaluation of green design solutions. 展开更多
关键词 RAILWAY Green performance Data collection METADATA Data classifcation BIM Image recognition
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Autonomous UAV 3D trajectory optimization and transmission scheduling for sensor data collection on uneven terrains
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作者 Andrey V.Savkin Satish C.Verma Wei Ni 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第12期154-160,共7页
This paper considers a time-constrained data collection problem from a network of ground sensors located on uneven terrain by an Unmanned Aerial Vehicle(UAV),a typical Unmanned Aerial System(UAS).The ground sensors ha... This paper considers a time-constrained data collection problem from a network of ground sensors located on uneven terrain by an Unmanned Aerial Vehicle(UAV),a typical Unmanned Aerial System(UAS).The ground sensors harvest renewable energy and are equipped with batteries and data buffers.The ground sensor model takes into account sensor data buffer and battery limitations.An asymptotically globally optimal method of joint UAV 3D trajectory optimization and data transmission schedule is developed.The developed method maximizes the amount of data transmitted to the UAV without losses and too long delays and minimizes the propulsion energy of the UAV.The developed algorithm of optimal trajectory optimization and transmission scheduling is based on dynamic programming.Computer simulations demonstrate the effectiveness of the proposed algorithm. 展开更多
关键词 Unmanned aerial system UAS Unmanned aerial vehicle UAV Wireless sensor networks UAS-Assisted data collection 3D trajectory optimization Data transmission scheduling
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Jade Collection of Emperor Qianlong in the Qing Dynasty
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作者 MA Lin 《Journal of Literature and Art Studies》 2023年第2期129-134,共6页
During the reign of emperor Qianlong of the Qing Dynasty,the political rule was relatively stable,the economy continued to develop,and both civil and martial situations flourished.The emperor’s love for jade articles... During the reign of emperor Qianlong of the Qing Dynasty,the political rule was relatively stable,the economy continued to develop,and both civil and martial situations flourished.The emperor’s love for jade articles made this period a peak in the development of Chinese jade culture.Based on jade articles of emperor Qianlong collected in the Palace Museum and related documents and archives,this paper tries to explore characteristics of this collection and emperor Qianlong’s collecting methods,then explains that this collection not only has the functions of aesthetics,but also has the meaning of morality,religion and politics. 展开更多
关键词 Emperor Qianlong jade collection endow jade with virtue
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Joint UAV 3D deployment and sensor power allocation for energy-efficient and secure data collection
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作者 王东 LI Guizhi +1 位作者 SUN Xiaojing WANG Changqing 《High Technology Letters》 EI CAS 2023年第3期223-230,共8页
Unmanned aerial vehicles(UAVs) are advantageous for data collection in wireless sensor networks(WSNs) due to its low cost of use,flexible deployment,controllable mobility,etc. However,how to cope with the inherent iss... Unmanned aerial vehicles(UAVs) are advantageous for data collection in wireless sensor networks(WSNs) due to its low cost of use,flexible deployment,controllable mobility,etc. However,how to cope with the inherent issues of energy limitation and data security in the WSNs is challenging in such an application paradigm. To this end,based on the framework of physical layer security,an optimization problem for maximizing secrecy energy efficiency(EE) of data collection is formulated,which focuses on optimizing the UAV’s positions and the sensors’ transmit power. To overcome the difficulties in solving the optimization problem,the methods of fractional programming and successive convex approximation are then adopted to gradually transform the original problem into a series of tractable subproblems which are solved in an iterative manner. As shown in simulation results,by the joint designs in the spatial domain of UAV and the power domain of sensors,the proposed algorithm achieves a significant improvement of secrecy EE and rate. 展开更多
关键词 physical layer security energy efficiency(EE) power allocation unmanned aerial vehicle(UAV) data collection wireless sensor network(WSN)
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