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An optimization method for shale gas gathering system-Consideration of reliability enhancement under earthquake-related uncertainties 被引量:1
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作者 Yan Wu Zi-Yuan Cui +2 位作者 Hai Lin Yu-Fei Wang Xiao Feng 《Petroleum Science》 SCIE CAS CSCD 2022年第5期2431-2447,共17页
Shale gas gathering systems are of great importance in gas fields for the efficient and reliable transportation of gas.In traditional design methods,pipeline layouts are optimized only from an economic point of view,w... Shale gas gathering systems are of great importance in gas fields for the efficient and reliable transportation of gas.In traditional design methods,pipeline layouts are optimized only from an economic point of view,where reliability is evaluated after optimization.However,reliability can be enhanced by spare pipelines so that both economic and reliable aspects are evaluated simultaneously.Based on the idea of enhancing reliability,this research proposes a methodology for optimizing the pipeline layout problem including well clustering,stations site selecting,and piping.Different topology arrangements and spare pipelines are investigated to enhance the production efficiency and reliability of the pipeline network under earthquake-related uncertainties.Reliability evaluation is converted into an economic one so that the objective of this work is to minimize the total annual cost.To solve such a complex problem,genetic algorithm,K-means algorithm,Geo Steiner algorithm,Kruskal algorithm,linear programming and Monte Carlo simulations are combined.A real-world case study illustrates the effectiveness of the proposed methodology and shows a 36.53%reduction in the total annual cost compared with the initial scheme. 展开更多
关键词 Shale gas gathering system Network topology RELIABILITY UNCERTAINTY
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Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network
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作者 Xue-Qiang Zhang Qing-Lin Cheng +2 位作者 Wei Sun Yi Zhao Zhi-Min Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期621-640,共20页
As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crud... As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems. 展开更多
关键词 Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction
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Slow-gathering areas of rivers, lakes, and reservoirs: Definition, estimation, and restoration
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作者 Ming Chen Ya-fei Li Chen Liu 《Water Science and Engineering》 EI CAS CSCD 2023年第1期113-116,共4页
Recently,humans have been facing serious water pollution problems that aggravate water resources shortages.By 2025,two-thirds of the world's population is likely to live in countries with moderate or severe water ... Recently,humans have been facing serious water pollution problems that aggravate water resources shortages.By 2025,two-thirds of the world's population is likely to live in countries with moderate or severe water shortages(Azizullah et al.,2011).Rivers,lakes,and reservoirs are important sources of water.Globally,there are approximately 8.5 million rivers(Linke et al.,2019),21.15 million natural lakes,and 1.427 million large reservoirs(Messager et al.,2016).Many of them have been contaminated due to urbanization,industrialization,and agricultural activities.In particular,all rivers,lakes,and reservoirs have their own slow-gathering areas(SGAs)where the input contaminants are easily stopped and deposited due to their non-open morphologies and low flow speeds. 展开更多
关键词 RESERVOIRS gathering ESTIMATION
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Deep Learning Based Face Mask Detection in Religious Mass Gathering During COVID-19 Pandemic
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作者 Abdullah S AL-Malaise AL-Ghamdi Sultanah MAlshammari Mahmoud Ragab 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1863-1877,共15页
Notwithstanding the religious intention of billions of devotees,the religious mass gathering increased major public health concerns since it likely became a huge super spreading event for the severe acute respiratory ... Notwithstanding the religious intention of billions of devotees,the religious mass gathering increased major public health concerns since it likely became a huge super spreading event for the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Most attendees ignored preventive measures,namely maintaining physical distance,practising hand hygiene,and wearing facemasks.Wearing a face mask in public areas protects people from spreading COVID-19.Artificial intelligence(AI)based on deep learning(DL)and machine learning(ML)could assist in fighting covid-19 in several ways.This study introduces a new deep learning-based Face Mask Detection in Religious Mass Gathering(DLFMD-RMG)technique during the COVID-19 pandemic.The DLFMD-RMG technique focuses mainly on detecting face masks in a religious mass gathering.To accomplish this,the presented DLFMD-RMG technique undergoes two pre-processing levels:Bilateral Filtering(BF)and Contrast Enhancement.For face detection,the DLFMD-RMG technique uses YOLOv5 with a ResNet-50 detector.In addition,the face detection performance can be improved by the seeker optimization algorithm(SOA)for tuning the hyperparameter of the ResNet-50 module,showing the novelty of the work.At last,the faces with and without masks are classified using the Fuzzy Neural Network(FNN)model.The stimulation study of the DLFMD-RMG algorithm is examined on a benchmark dataset.The results highlighted the remarkable performance of the DLFMD-RMG model algorithm in other recent approaches. 展开更多
关键词 Religious mass gathering Hajj and Umrah covid-19 pandemic face mask computer vision deep learning
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Dataset of Large Gathering Images for Person Identification and Tracking
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作者 Adnan Nadeem Amir Mehmood +7 位作者 Kashif Rizwan Muhammad Ashraf Nauman Qadeer Ali Alzahrani Qammer H.Abbasi Fazal Noor Majed Alhaisoni Nadeem Mahmood 《Computers, Materials & Continua》 SCIE EI 2023年第3期6065-6080,共16页
This paper presents a large gathering dataset of images extracted from publicly filmed videos by 24 cameras installed on the premises of Masjid Al-Nabvi,Madinah,Saudi Arabia.This dataset consists of raw and processed ... This paper presents a large gathering dataset of images extracted from publicly filmed videos by 24 cameras installed on the premises of Masjid Al-Nabvi,Madinah,Saudi Arabia.This dataset consists of raw and processed images reflecting a highly challenging and unconstraint environment.The methodology for building the dataset consists of four core phases;that include acquisition of videos,extraction of frames,localization of face regions,and cropping and resizing of detected face regions.The raw images in the dataset consist of a total of 4613 frames obtained fromvideo sequences.The processed images in the dataset consist of the face regions of 250 persons extracted from raw data images to ensure the authenticity of the presented data.The dataset further consists of 8 images corresponding to each of the 250 subjects(persons)for a total of 2000 images.It portrays a highly unconstrained and challenging environment with human faces of varying sizes and pixel quality(resolution).Since the face regions in video sequences are severely degraded due to various unavoidable factors,it can be used as a benchmark to test and evaluate face detection and recognition algorithms for research purposes.We have also gathered and displayed records of the presence of subjects who appear in presented frames;in a temporal context.This can also be used as a temporal benchmark for tracking,finding persons,activity monitoring,and crowd counting in large crowd scenarios. 展开更多
关键词 Large crowd gatherings a dataset of large crowd images highly uncontrolled environment tracking missing persons face recognition activity monitoring
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Study on Influencing Factors and Mechanism of Scientific and Technological Innovation Talents Gathering in Zhejiang Province
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作者 Liang Ma Qiqi He 《Open Journal of Applied Sciences》 2023年第12期2371-2386,共16页
This paper systematically studies the influencing factors and mechanism of the agglomeration of scientific and technological innovation talents in Zhejiang Province. The findings are as follows: Firstly, environmental... This paper systematically studies the influencing factors and mechanism of the agglomeration of scientific and technological innovation talents in Zhejiang Province. The findings are as follows: Firstly, environmental factors such as marketization level, financial development, opening to the outside world, infrastructure construction, medical resources, educational resources, cultural resources and policy support have a positive impact on the agglomeration of scientific and technological talents in Zhejiang Province;Secondly, in the transmission mechanism of the influence of various environmental factors on the concentration of scientific and technological talents in Zhejiang, economic development plays an intermediary role, and the effect is obvious. Various environmental factors indirectly affect the concentration of scientific and technological talents in Zhejiang through economic development. Finally, although both the level and quality of economic development have significant effect on the total concentration of scientific and technological talents in Zhejiang, the mediating effect of economic development level is more significant. These studies are for Zhejiang Province. It provides a theoretical basis for cultivating high-end talents and realizing the agglomeration of scientific and technological innovation talents. 展开更多
关键词 Scientific and Technological Innovation Talents Talent gathering Action Mechanism
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Editorial for Multiscale&Multifield Coupling in Geomechanics
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作者 Min Wang Pengzhi Pan +1 位作者 Andrew H.C.Chan Y.T.Feng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1919-1921,共3页
We are delighted to serve as guest editors for this special issue in the Journal of Rock Mechanics and Geotechnical Engineering.The purpose of this special issue is dedicated to gathering the latest research work on M... We are delighted to serve as guest editors for this special issue in the Journal of Rock Mechanics and Geotechnical Engineering.The purpose of this special issue is dedicated to gathering the latest research work on Multiscale&Multifield Coupling in Geomechanics,where we delve into the intricate interplay of various fields and scales that govern the behavior of geomaterials.In total,30 manuscripts from USA,China,UK,Germany,Canada,India and United Arab Emirates are selected to be included in this issue. 展开更多
关键词 materials. gathering MECHANICS
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Open to Chinese Democracy
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作者 ROBERT WALKER 《China Today》 2024年第3期46-48,共3页
The National People’s Congress meets every year for about a week in March.But there is much more to China’s democracy.SOME 2,977 elected deputies will be attending the second plenary meeting of the 14th National Peo... The National People’s Congress meets every year for about a week in March.But there is much more to China’s democracy.SOME 2,977 elected deputies will be attending the second plenary meeting of the 14th National People’s Congress at the Great Hall of the People in Beijing in early March.This,the world’s largest legislative body,is the most striking manifestation of China’s governance system,whole-process people’s democracy.For outsiders,the gathering seems symbolic and ceremonial.However,the deliberation undertaken by the unpaid deputies in the week that they are together is merely the most visible element in a complex consultative system of government. 展开更多
关键词 gathering striking system
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Matters of Life and Death
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作者 Gao Yuan 《China Report ASEAN》 2024年第4期50-53,共4页
In a secluded corner of a café,several young people sit around a small square table laden with an assortment of drinks and desserts.They take turns introducing themselves.The setup is reminiscent of speed dating ... In a secluded corner of a café,several young people sit around a small square table laden with an assortment of drinks and desserts.They take turns introducing themselves.The setup is reminiscent of speed dating or a team-building meeting,but the content of discussion is far from either.The unique event is known as Death Café.The purpose of the gathering is to discuss issues related to death.Participants express their thoughts,share experiences and rarely exposed emotions,and offer mutual support amidst a whirlwind of intense feelings. 展开更多
关键词 gathering mutual TURNS
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Recent and Forthcoming Events
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《China & The World Cultural Exchange》 2024年第4期5-5,共1页
The‘Spring Cup’Table Tennisand Badminton International Championship Held by China Cultural Centerin Benin。On March 16,China Cultural Center in Benin,together with the Benin Badminton and Table Tennis Association,he... The‘Spring Cup’Table Tennisand Badminton International Championship Held by China Cultural Centerin Benin。On March 16,China Cultural Center in Benin,together with the Benin Badminton and Table Tennis Association,held the 2024"Spring Cup"Table Tennis and Badminton International Championship at the Palace of Arts,Entertainment and Sports in Cotonou.More than 100 athletes from China,Benin,Togo,India and other countries gathered to show their talents. 展开更多
关键词 gathered COMING INDIA
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Enduring Importance
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作者 HU FAN 《ChinAfrica》 2024年第4期32-33,共2页
On 5 March,national and global spotlight turned to the Great Hall of the People in Beijing where around 3,000 deputies gathered to open the second session of the 14th National People’s Congress(NPC).Over a span of se... On 5 March,national and global spotlight turned to the Great Hall of the People in Beijing where around 3,000 deputies gathered to open the second session of the 14th National People’s Congress(NPC).Over a span of seven days,the deputies,representing all of China’s ethnic groups,regions and sectors,discussed and decided on a range of issues critical for the country’s development. 展开更多
关键词 representing development. gathered
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A Democracy That Works Western democracies have failed to address people’s livelihood concerns while the Chinese practice has made notable achievements
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作者 CHARLES ONUNAIJU 《ChinAfrica》 2024年第5期16-17,共2页
More than 200 scholars,researchers,former government o!cials and party leaders from over 50 countries gathered in the sprawling building of the Chinese Academy of History in Beijing on 20 March for the third Internati... More than 200 scholars,researchers,former government o!cials and party leaders from over 50 countries gathered in the sprawling building of the Chinese Academy of History in Beijing on 20 March for the third International Forum on Democracy:The Shared Human Values.The forum debated the concept of democracy,its trajectories and prospects,and,more importantly,how it can be made to work and deliver tangible results for di"erent countries. 展开更多
关键词 DEMOCRACY gathered DEBATE
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Data Gathering in Wireless Sensor Networks Via Regular Low Density Parity Check Matrix 被引量:1
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作者 Xiaoxia Song Yong Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第1期83-91,共9页
A great challenge faced by wireless sensor networks(WSNs) is to reduce energy consumption of sensor nodes. Fortunately, the data gathering via random sensing can save energy of sensor nodes. Nevertheless, its randomne... A great challenge faced by wireless sensor networks(WSNs) is to reduce energy consumption of sensor nodes. Fortunately, the data gathering via random sensing can save energy of sensor nodes. Nevertheless, its randomness and density usually result in difficult implementations, high computation complexity and large storage spaces in practical settings. So the deterministic sparse sensing matrices are desired in some situations. However,it is difficult to guarantee the performance of deterministic sensing matrix by the acknowledged metrics. In this paper, we construct a class of deterministic sparse sensing matrices with statistical versions of restricted isometry property(St RIP) via regular low density parity check(RLDPC) matrices. The key idea of our construction is to achieve small mutual coherence of the matrices by confining the column weights of RLDPC matrices such that St RIP is satisfied. Besides, we prove that the constructed sensing matrices have the same scale of measurement numbers as the dense measurements. We also propose a data gathering method based on RLDPC matrix. Experimental results verify that the constructed sensing matrices have better reconstruction performance, compared to the Gaussian, Bernoulli, and CSLDPC matrices. And we also verify that the data gathering via RLDPC matrix can reduce energy consumption of WSNs. 展开更多
关键词 Data gathering regular low density parity check(RLDPC) matrix sensing matrix signal reconstruction wireless sensor networks(WSNs)
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Flow Characteristics of Crude Oil with High Water Fraction during Non-heating Gathering and Transportation 被引量:1
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作者 LüYuling Tan Hao +2 位作者 Li Jiao Yang Donghai Xu Peiyang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2021年第1期88-97,共10页
In order to ensure the safety of the non-heating gathering and transportation processes for high water fraction crude oil,the effect of temperature,water fraction,and flow rate on the flow characteristics of crude oil... In order to ensure the safety of the non-heating gathering and transportation processes for high water fraction crude oil,the effect of temperature,water fraction,and flow rate on the flow characteristics of crude oil with high water fraction was studied in a flow experimental system of the X Oilfield.Four distinct flow patterns were identified by the photographic and local sampling techniques.Especially,three new flow patterns were found to occur below the pour point of crude oil,including EW/O&W stratified flow with gel deposition,EW/O&W intermittent flow with gel deposition,and water single-phase flow with gel deposition.Moreover,two characteristic temperatures,at which the change rate of pressure drop had changed obviously,were found during the change of pressure drop.The characteristic temperature of the first congestion of gel deposition in the pipeline was determined to be the safe temperature for the non-heating gathering and transportation of high water cut crude oil,while the pressure drop reached the peak at this temperature.An empirical formula for the safe temperature was established for oil-water flow with high water fraction/low fluid production rate.The results can serve as a guide for the safe operation of the non-heating gathering and transportation of crude oil in high water fraction oilfields. 展开更多
关键词 crude oil with high water fraction non-heating gathering and transportation flow pattern pressure drop safe temperature
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Single Mobile Sink Based Energy Efficiency and Fast Data Gathering Protocol for Wireless Sensor Networks 被引量:1
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作者 Shivkumar S. Jawaligi G. S. Biradar 《Wireless Sensor Network》 2017年第4期117-144,共28页
Recently, the exponential rise in communication system demands has motivated global academia-industry to develop efficient communication technologies to fulfill energy efficiency and Quality of Service (QoS) demands. ... Recently, the exponential rise in communication system demands has motivated global academia-industry to develop efficient communication technologies to fulfill energy efficiency and Quality of Service (QoS) demands. Wireless Sensor Network (WSN) being one of the most efficient technologies possesses immense potential to serve major communication purposes including civil, defense and industrial purposes etc. The inclusion of sensor-mobility with WSN has broadened application horizon. The effectiveness of WSNs can be characterized by its ability to perform efficient data gathering and transmission to the base station for decision process. Clustering based routing scheme has been one of the dominating techniques for WSN systems;however key issues like, cluster formation, selection of the number of clusters and cluster heads, and data transmission decision from sensors to the mobile sink have always been an open research area. In this paper, a robust and energy efficient single mobile sink based WSN data gathering protocol is proposed. Unlike existing approaches, an enhanced centralized clustering model is developed on the basis of expectation-maximization (EEM) concept. Further, it is strengthened by using an optimal cluster count estimation technique that ensures that the number of clusters in the network region doesn’t introduce unwanted energy exhaustion. Meanwhile, the relative distance between sensor node and cluster head as well as mobile sink is used to make transmission (path) decision. Results exhibit that the proposed EEM based clustering with optimal cluster selection and optimal dynamic transmission decision enables higher throughput, fast data gathering, minima delay and energy consumption, and higher 展开更多
关键词 Wireless Sensor Network Data gathering SINGLE Mobile SINK NODE CENTRALIZED Clustering EXPECTATION-MAXIMIZATION
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FAILURE ASSESSMENT OF DEFECTIVE GATHERING TUBE UNDER HIGH PRESSURE
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作者 Zhang Wenge Li Jianrong Yu JilinKey Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, CAS, Hefei 230027, ChinaChen Xuedong Zhang Haibo Wang Bing Hefei General Machinery Research Institute 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第2期189-192,共4页
A numerical model on stress assessment of a defective elliptic gathering tubeused in the heat recovery boiler of a pyrolyzer is built up. The effect of local defects on thecarrying capacity of the tube is analyzed by ... A numerical model on stress assessment of a defective elliptic gathering tubeused in the heat recovery boiler of a pyrolyzer is built up. The effect of local defects on thecarrying capacity of the tube is analyzed by using the MSC/NASTRAN finite element code, and thecritical size of defects is obtained. Then, two numerical models of damaged tube with local andintegral reinforcements, respectively, are also calculated. Stress classification and assessmentsare provided by applying the ASME and JB4732-1995 standard. Some guidance and suggestions about thetube reinforcements and the prediction of the remaining life of the structure for engineeringpractice are discussed. 展开更多
关键词 gathering tube Heat recovery boiler Initial damage Failure assessment Numerical simulation
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A Power Graded Data Gathering Mechanism for Wireless Sensor Networks
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作者 BI Yan-Zhong YAN Ting-Xin +1 位作者 SUN Li-Min WU Zhi-Mei 《自动化学报》 EI CSCD 北大核心 2006年第6期881-891,共11页
The data gathering manner of wireless sensor networks, in which data is forwarded towards the sink node, would cause the nodes near the sink node to transmit more data than those far from it. Most data gathering mecha... The data gathering manner of wireless sensor networks, in which data is forwarded towards the sink node, would cause the nodes near the sink node to transmit more data than those far from it. Most data gathering mechanisms nowdo not do well in balancing the energy consumption among nodes with different distances to the sink, thus they can hardly avoid the problem that nodes near the sink consume energy more quickly, which may cause the network rupture from the sink node. This paper presents a data gathering mechanism called PODA, which grades the output power of nodes according to their distances from the sink node. PODA balances energy consumption by setting the nodes near the sink with lower output power and the nodes far from the sink with higher output power. Simulation results show that the PODA mechanism can achieve even energy consumption in the entire network, improve energy efficiency and prolong the network lifetime. 展开更多
关键词 Wireless sensor network energy balance power grade data gathering
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China to Host UN Ecological Gathering
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《China Today》 2019年第5期7-7,共1页
China will host this year’s global World Environment Day celebrations on June 5 in Hangzhou, Zhejiang Province, on the theme of air pollution. Joyce Msuya, acting director of the United Nations Environment Programme,... China will host this year’s global World Environment Day celebrations on June 5 in Hangzhou, Zhejiang Province, on the theme of air pollution. Joyce Msuya, acting director of the United Nations Environment Programme, welcomed China’s selection as host.“The country has demonstrated tremendous leadership in tackling air pollution domestically. It can now help spur the world to greater action.” With its growing green energy sector, China has emerged as a climate leader. The country owns half of the world’s electric cars and 99 percent of the world’s electric buses, according to UN. 展开更多
关键词 China UN ECOLOGICAL gathering
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Dissociate Hb of materials plasma gathering by Autopheresis-C 200 investigate and analyse by content
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《中国输血杂志》 CAS CSCD 2001年第S1期423-,共1页
关键词 HB Dissociate Hb of materials plasma gathering by Autopheresis-C 200 investigate and analyse by content
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Analysis of the Coupling and Coordination Degree between the Development of Marine Industry and the Gathering of Marine Talents
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作者 Jiaji WANG Qunzhen QU 《Meteorological and Environmental Research》 CAS 2021年第3期47-49,52,共4页
The development status of China's marine industry in recent years was qualitatively analyzed,and it is found that the scale of China's marine economy continued to expand,and the industrial structure has been c... The development status of China's marine industry in recent years was qualitatively analyzed,and it is found that the scale of China's marine economy continued to expand,and the industrial structure has been continuously optimized.Then,the coupling and coordination degree between the development of marine industry and the gathering of marine talents were analyzed quantitatively,and it is found that the development of marine industry generally promoted the gathering of marine talents,but the promotion of each industry was weak.The influence of the development of marine industry on the gathering of marine talents should be strengthened.It is proposed that the development of marine industry should be promoted from the aspects of strengthening the planning level of industrial development,improving the efficiency of resource allocation,promoting the innovation and development of marine industry,and strengthening the management of marine talents,so as to enhance the influence of marine industry on the gathering of marine talents and form a benign interaction between talents and industry. 展开更多
关键词 Marine industry Marine talents gathering of marine talents Coupling and coordination degree
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