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Coordinated restoration optimization of power-gas integrated energy system with mobile emergency sources 被引量:2
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作者 Lili Hao Wangyu Hu +4 位作者 Chuan Wang Guangzong Wang Yue Sun Jun Chen Xueping Pan 《Global Energy Interconnection》 EI CAS CSCD 2023年第2期205-227,共23页
In an integrated energy system(IES) composed of multiple subsystems, energy coupling causes an energy supply blockage or shutdown in one subsystem, thereby affecting the energy flow distribution optimization of other ... In an integrated energy system(IES) composed of multiple subsystems, energy coupling causes an energy supply blockage or shutdown in one subsystem, thereby affecting the energy flow distribution optimization of other subsystems.The energy supply should be globally optimized during the IES energy supply restoration process to produce the highest restoration net income. Mobile emergency sources can be quickly and flexibly connected to supply energy after an energy outage to ensure a reliable supply to the system, which adds complexity to the decision. This study focuses on a powergas IES with mobile emergency sources and analyzes the coupling relationship between the gas distribution system and the power distribution system in terms of sources, networks, and loads, and the influence of mobile emergency source transportation. The influence of the transient process caused by the restoration operation of the gas distribution system on the power distribution system is also discussed. An optimization model for power-gas IES restoration was established with the objective of maximizing the net income. The coordinated restoration optimization decision-making process was also built to realize the decoupling iteration of the power-gas IES, including system status recognition, mobile emergency source dispatching optimization, gas-to-power gas flow optimization, and parallel intra-partition restoration scheme optimization for both the power and gas distribution systems. A simulation test power-gas IES consisting of an 81-node medium-voltage power distribution network, an 89-node medium-pressure gas distribution network, and four mobile emergency sources was constructed. The simulation analysis verified the efficiency of the proposed coordinated restoration optimization method. 展开更多
关键词 Coordinated restoration optimization integrated energy system Power-gas decoupling Gas-to-power flow optimization Mobile emergency source
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Source Text Borrowing in Summary of Integrated Writing
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作者 XIE Xin-ran 《Journal of Literature and Art Studies》 2023年第9期699-703,共5页
Integrated writing tasks,requiring writers to summarize source content and integrate their ideas or experience with those in the source text,are widely used in standardized tests of English proficiency.Integrated writ... Integrated writing tasks,requiring writers to summarize source content and integrate their ideas or experience with those in the source text,are widely used in standardized tests of English proficiency.Integrated writing adds an element not found in traditional independent writing:the use of source text material.Recently,concern has been raised that over-reliance on source texts in integrated writing may lead to plagiarism as well as inaccurate assessment which calls for further investigation.Research on L2 students’writing using sources has broadened its focus from transgressive citing practices to stages of skill development in this complicated literacy,the successive challenges students face,and how instruction might be of benefit.Previous literature mainly focused on source use in academic writing and seldom considered summary writing in standardized tests,while summary strategy is particularly important in standardized tests,in which summary accounts for a significant part of the assessment criteria.Given that a series of previous literature have indicated that source text use,source texts,and prompts are associated with the quality of summary writing,this article reviews the source text borrowing in the summary of integrated writing to further explore the relationship between some variables and the quality of summary writing and therefore finds some research gaps in this field. 展开更多
关键词 summary writing source text borrowing integrated writing PARAPHRASING
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Application of integrated geophysical techniques in geothermal exploration in Binhai County, Jiangsu Province
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作者 Juncheng Wang Shiyin Gao +3 位作者 Jianguo Wang Lin Li Xiaoyan Gong Jinbao Su 《Deep Underground Science and Engineering》 2024年第3期338-348,共11页
Integrated geophysical technology is a necessary and effective means for geothermal exploration.However,integration of geophysical technology for large‐scale surveys with those for geothermal reservoir localization i... Integrated geophysical technology is a necessary and effective means for geothermal exploration.However,integration of geophysical technology for large‐scale surveys with those for geothermal reservoir localization is still in development.This study used the controlled source audio‐frequency magnetotelluric method technology for large‐scale exploration to obtain underground electrical structure information and micromotion detection technology to obtain underground wave velocity structure information.The combination of two detection technologies was used for local identification of geothermal reservoirs.Further,auxiliary correction and inversion constraint were implemented through the audio magnetotelluric sounding technology for maximum authenticity restoration of the near‐and transition‐field data.Through these technology improvements,a geothermal geological model was established for the Binhai County of Jiangsu Province in China and potential geothermal well locations were identified.On this basis,a geothermal well was drilled nearly 3000m deep,with a daily water volume of over 2000m3/day and a geothermal water temperature of 51°C at the well head.It is found that predictions using the above integrated geophysical exploration technology are in good agreement with the well geological formation data.This integrated geophysical technology can be effectively applied for geothermal exploration with high precision and reliability. 展开更多
关键词 controlled source audio frequency magnetotelluric method(CSAMT) geothermal exploration integrated geophysical technology micromotion detection technology
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Watts-level ultraviolet-CLED integrated light sources for efficient surface and air sterilization 被引量:1
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作者 Wei Luo Tai Li +7 位作者 Yongde Li Houjin Wang Ye Yuan Shangfeng Liu Weiyun Wang Qi Wang Junjie Kang Xinqiang Wang 《Journal of Semiconductors》 EI CAS CSCD 2022年第7期61-67,共7页
With the epidemic of the coronavirus disease(COVID-19) infection, AlGaN-based ultraviolet-C light emitting diodes(UVC-LEDs) have attracted widespread attention for their sterilization application. However, the sterili... With the epidemic of the coronavirus disease(COVID-19) infection, AlGaN-based ultraviolet-C light emitting diodes(UVC-LEDs) have attracted widespread attention for their sterilization application. However, the sterilization characters of high power integrated light sources(ILSs) haven’t been widely investigated before utilizing in public sanitary security. In this work,by integrating up to 195 UVC-LED chips, high power UVC-LED ILSs with a light output power(LOP) of 1.88 W were demonstrated. The UVC-LED ILSs were verified to have efficient and rapid sterilization capability, which have achieved more than99.9% inactivation rate of several common pathogenic microorganisms within 1 s. In addition, the corresponding air sterilization module based on them was also demonstrated to kill more than 97% of Staphylococcus albus in the air of 20 m3 confined room within 30 min. This work demonstrates excellent sterilization ability of UVC-LED ILSs with high LOP, revealing great potential of UVC-LEDs in sterilization applications in the future. 展开更多
关键词 ultraviolet-C LED integrated light source surface sterilization air sterilization
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3D Geological Modeling with Multi-source Data Integration in Polymetallic Region:A Case Study of Luanchuan,Henan Province,China 被引量:1
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作者 Gongwen Wang~(1,2),Shouting Zhang~(1,2),Changhai Yan~3,Yaowu Song~3,Limei Wang~1 1.School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China. 2.State Key laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing 100083,China 3.Henan Institute of Geological Survey,Zhengzhou 450007,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期166-167,共2页
The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luan... The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luanchuan,the case study area,southwestern Henan Province,is an important molybdenum-tungsten -lead-zinc polymetallic belt in China. 展开更多
关键词 3D GEOLOGICAL modeling multi-source data MINERAL exploration METALLOGENIC model virtual GEOLOGICAL section Luanchuan POLYMETALLIC REGION
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Integrated Joint Source-Channel Symbol-by-Symbol Decoding of Variable-Length Codes Using 3-D MAP Sequence Estimation 被引量:1
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作者 WU Jing CHEN Shuzhen 《Wuhan University Journal of Natural Sciences》 CAS 2007年第3期471-475,共5页
Most of multimedia schemes employ variable-length codes (VLCs) like Huffman code as core components in obtaining high compression rates. However VLC methods are very sensitive to channel noise. The goal of this pape... Most of multimedia schemes employ variable-length codes (VLCs) like Huffman code as core components in obtaining high compression rates. However VLC methods are very sensitive to channel noise. The goal of this paper is to salvage as many data from the damaged packets as possible for higher audiovisual quality. This paper proposes an integrated joint source-channel decoder (I-JSCD) at a symbol-level using three-dimensional (3-D) trellis representation for first-order Markov sources encoded with VLC source code and convolutional channel code. This method combines source code and channel code state-spaces and bit-lengths to construct a two-dimensional (2-D) state-space, and then develops a 3-D trellis and a maximum a-posterior (MAP) algorithm to estimate the source sequence symbol by symbol. Experiment results demonstrate that our method results in significant improvement in decoding performance, it can salvage at least half of (50%) data in any channel error rate, and can provide additional error resilience to VLC stream like image, audio, video stream over high error rate links. 展开更多
关键词 integrated joint source-channel decoding (I-JSCD) variable-length code (VLC) exp-Golomb code convolutional code: maximum a-oosteriori (MAP)
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Integrated Joint Source-Channel Decoding for H.264 Video Transmission
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作者 WU Jing CHEN Shuzhen 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期1057-1062,共6页
This paper proposes an integrated joint source-channel decoder (I-JSCD) using Max-Log-MAP method for sources encoded with exp-Golomb codes and convolutional codes, and proposes a system applying this method to decod... This paper proposes an integrated joint source-channel decoder (I-JSCD) using Max-Log-MAP method for sources encoded with exp-Golomb codes and convolutional codes, and proposes a system applying this method to decoding the VLC data, e.g. motion vector differences (MVDs), of H.264 across an AWGN channel. This method combines the source code state-space and the channel code state-space together to construct a joint state-space, develops a 3-D trellis and a maximum a-posterior (MAP) algorithm to estimate the source sequence symbol by symbol, and then uses max-log approximation to simplify the algorithm. Experiments indicate that the proposed system gives significant improvements on peak signal-to-noise ratio (PSNR) (maximum about 15 dB) than a separate scheme. This also leads to a higher visual quality of video stream over a highly noisy channel. 展开更多
关键词 H.264 motion vector difference (MVD) integrated joint source-channel decoding (I-JSCD) variable-length code (VLC) exp-Golomb code MAX-LOG-MAP
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Study on Characteristics of 3-D Translating-Pulsating Source Green Function of Deep-Water Havelock Form and Its Fast Integration Method 被引量:19
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作者 许勇 董文才 《China Ocean Engineering》 SCIE EI 2011年第3期365-380,共16页
The singularities, oscillatory performances and the contributing factors to the 3-'D translating-pulsating source Green function of deep-water Havelock form which consists of a local disturbance part and a far-field ... The singularities, oscillatory performances and the contributing factors to the 3-'D translating-pulsating source Green function of deep-water Havelock form which consists of a local disturbance part and a far-field wave-like part, are analyzed systematically. Relative numerical integral methods about the two parts are presented in this paper. An improved method based on LOBATTO rule is used to eliminate singularities caused respectively by infinite discontinuity and jump discontinuous node from the local disturbance part function, which makes the improvement of calculation efficiency and accuracy possible. And variable substitution is applied to remove the singularity existing at the end of the integral interval of the far-field wave-like part function. Two auxiliary techniques such as valid interval calculation and local refinement of integral steps technique in narrow zones near false singularities are applied so as to avoid unnecessary integration of invalid interval and improve integral accordance. Numerical test results have proved the efficiency and accuracy in these integral methods that thus can be applied to calculate hydrodynamic performance of floating structures moving in waves. 展开更多
关键词 translating-pulsating source Green's function singularity highly oscillatory function integration method
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Two new integrable couplings of the soliton hierarchies with self-consistent sources 被引量:7
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作者 夏铁成 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期49-56,共8页
A kind of integrable coupling of soliton equations hierarchy with self-consistent sources associated with s/(4) has been presented (Yu F J and Li L 2009 Appl. Math. Comput. 207 171; Yu F J 2008 Phys. Lett. A 372 6... A kind of integrable coupling of soliton equations hierarchy with self-consistent sources associated with s/(4) has been presented (Yu F J and Li L 2009 Appl. Math. Comput. 207 171; Yu F J 2008 Phys. Lett. A 372 6613). Based on this method, we construct two integrable couplings of the soliton hierarchy with self-consistent sources by using the loop algebra sl(4). In this paper, we also point out that there are some errors in these references and we have corrected these errors and set up new formula. The method can be generalized to other soliton hierarchy with self-consistent sources. 展开更多
关键词 TC hierarchy generalized Burgers hierarchy self-consistent sources integrable couplings loop algebra
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A New Integrable Couplings of Classical-Boussinesq Hierarchy with Self-Consistent Sources 被引量:3
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作者 葛健芽 夏铁成 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期1-6,共6页
A kind of integrable couplings of soliton equations hierarchy with self-consistent sources associated with sl(4) is presented by Yu. Based on this method, we construct a new integrable couplings of the classical-Bou... A kind of integrable couplings of soliton equations hierarchy with self-consistent sources associated with sl(4) is presented by Yu. Based on this method, we construct a new integrable couplings of the classical-Boussinesq hierarchy with self-consistent sources by using of loop algebra sl(4). In this paper, we also point out that there exist some errors in Yu's paper and have corrected these errors and set up new formula. The method can be generalized other soliton hierarchy with self-consistent sources. 展开更多
关键词 the classical-Boussinesq hierarchy self-consistent sources integrable couplings loop algebra
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Importance of kelp-derived organic carbon to the scallop Chlamys farreri in an integrated multi-trophic aquaculture system 被引量:3
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作者 许强 高菲 杨红生 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第2期322-329,共8页
Bivalves and seaweeds are important cleaners that are widely used in integrated multi-trophic aquaculture (IMTA) systems. A beneficial relationship between seaweed and bivalve in the seaweed- based IMTA system has b... Bivalves and seaweeds are important cleaners that are widely used in integrated multi-trophic aquaculture (IMTA) systems. A beneficial relationship between seaweed and bivalve in the seaweed- based IMTA system has been confirmed, but the trophic importance of seaweed-derived particulate organic materials to the co-cultured bivalve is still unclear. We evaluated the trophic importance of the kelp Saccharinajaponica to the co-cultured scallop Chlamysfarreri in a typical IMTA farm in Sungo Bay (Weihai, North China). The dynamics of detritus carbon in the water were monitored during the culturing period. The proportion of kelp-derived organic matter in the diet of the co-cultured scallop was assessed via the stable carbon isotope method. Results showed that the detritus carbon in the water ranged from 75.52 to 265.19 ~tg/L, which was 25.6% to 73.8% of total particulate organic carbon (TPOC) during the study period. The amount of detritus carbon and its proportion in the TPOC changed throughout the culture cycle of the kelp. Stable carbon isotope analysis showed that the cultured scallop obtained 14.1% to 42.8% of its tissue carbon from the kelp, and that the percentages were closely correlated with the proportion of detritus carbon in the water (F=0.993, P=0.003). Evaluation showed that for 17 000 tons (wet weight) of annual scallop production, the kelp contributed about 139.3 tons of carbon (535.8 tons of dry mass). This confirms that cultured kelp plays a similar trophic role in IMTA systems as it does in a natural kelp bed. It is a major contributor to the detritus pool and supplies a vital food source to filter-feeding scallops in the IMTA system, especially during winter and early spring when phytoplankton are scarce. 展开更多
关键词 integrated multi-trophic aquaculture (IMTA) KELP BIVALVE DETRITUS food source stable carbonisotope
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Integrable Coupling System of JM Equations Hierarchy with Self-Consistent Sources 被引量:2
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作者 于发军 李丽 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期6-12,共7页
We propose a systematic method for generalizing the integrable couplings of soliton eqhations hierarchy with self-consistent sources associated with s/(4). The JM equations hierarchy with self-consistent sources is ... We propose a systematic method for generalizing the integrable couplings of soliton eqhations hierarchy with self-consistent sources associated with s/(4). The JM equations hierarchy with self-consistent sources is derived. Furthermore, an integrable couplings of the JM soliton hierarchy with self-consistent sources is presented by using of the loop algebra sl(4). 展开更多
关键词 JM equations hierarchy self-consistent sources integrable couplings
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Nonlinear integrable couplings of a nonlinear Schrdinger-modified Korteweg de Vries hierarchy with self-consistent sources 被引量:1
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作者 杨红卫 董焕河 尹宝树 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第10期22-28,共7页
By means of the Lie algebra B 2,a new extended Lie algebra F is constructed.Based on the Lie algebras B 2 and F,the nonlinear Schro¨dinger-modified Korteweg de Vries(NLS-mKdV) hierarchy with self-consistent sou... By means of the Lie algebra B 2,a new extended Lie algebra F is constructed.Based on the Lie algebras B 2 and F,the nonlinear Schro¨dinger-modified Korteweg de Vries(NLS-mKdV) hierarchy with self-consistent sources as well as its nonlinear integrable couplings are derived.With the help of the variational identity,their Hamiltonian structures are generated. 展开更多
关键词 nonlinear integrable couplings NLS-mKdV hierarchy self-consistent sources
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A multi-source data fusion modeling method for debris flow prevention engineering 被引量:1
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作者 XU Qing-yang YE Jian LYU Yi-jie 《Journal of Mountain Science》 SCIE CSCD 2021年第4期1049-1061,共13页
The Digital Elevation Model(DEM)data of debris flow prevention engineering are the boundary of a debris flow prevention simulation,which provides accurate and reliable DEM data and is a key consideration in debris flo... The Digital Elevation Model(DEM)data of debris flow prevention engineering are the boundary of a debris flow prevention simulation,which provides accurate and reliable DEM data and is a key consideration in debris flow prevention simulations.Thus,this paper proposes a multi-source data fusion method.First,we constructed 3D models of debris flow prevention using virtual reality technology according to the relevant specifications.The 3D spatial data generated by 3D modeling were converted into DEM data for debris flow prevention engineering.Then,the accuracy and applicability of the DEM data were verified by the error analysis testing and fusion testing of the debris flow prevention simulation.Finally,we propose the Levels of Detail algorithm based on the quadtree structure to realize the visualization of a large-scale disaster prevention scene.The test results reveal that the data fusion method controlled the error rate of the DEM data of the debris flow prevention engineering within an allowable range and generated 3D volume data(obj format)to compensate for the deficiency of the DEM data whereby the 3D internal entity space is not expressed.Additionally,the levels of detailed method can dispatch the data of a large-scale debris flow hazard scene in real time to ensure a realistic 3D visualization.In summary,the proposed methods can be applied to the planning of debris flow prevention engineering and to the simulation of the debris flow prevention process. 展开更多
关键词 Debris flow prevention Level of detail Debris flow simulation multi platform fusion multi source data fusion
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Hydrogeochemical Characteristics and Groundwater Inrush Source Identification for a Multi-aquifer System in a Coal Mine 被引量:9
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作者 ZHANG Haitao XU Guangquan +3 位作者 CHEN Xiaoqing WEI Jian YU Shitao YANG Tingting 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第6期1922-1932,共11页
Correct identification of water inrush sources is particularly important to prevent and control mine water disasters.Hydrochemical analysis,Fisher discriminant analysis,and geothermal verification analysis were used t... Correct identification of water inrush sources is particularly important to prevent and control mine water disasters.Hydrochemical analysis,Fisher discriminant analysis,and geothermal verification analysis were used to identify and verify the water sources of the multi-aquifer groundwater system in Gubei coal mine,Anhui Province,North China.Results show that hydrochemical water types of the Cenozoic top aquifer included HCO3-Na+K-Ca,HCO3-Na+K-Mg and HCO3-Na+K,and this aquifer was easily distinguishable from other aquifers because of its low concentration of Na++K+and Cl-.The Cenozoic middle and bottom aquifers,the Permian fissure aquifer,and the Taiyuan and Ordovician limestone aquifers were mainly characterized by the Cl-Na+K and SO4-Cl-Na+K or HCO3-Cl-Na+K water types,and their hydrogeochemistries were similar.Therefore,water sources could not be identified via hydrochemical analysis.Fisher model was established based on the hydrogeochemical characteristics,and its discrimination rate was 89.19%.Fisher discrimination results were improved by combining them with the geothermal analysis results,and this combination increased the identification rate to 97.3%and reasonably explained the reasons behind two water samples misjudgments.The methods described herein are also applicable to other mines with similar geological and hydrogeological conditions in North China. 展开更多
关键词 water inrush source multi-aquifer HYDROGEOCHEMISTRY Fisher discrimination geothermal verification analysis coal mine
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Coordinated control of coastal multi-source multi-load system with desalination load: a review 被引量:3
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作者 Ming Zhong Lu Jin +3 位作者 Jiyu Xia Ling Cheng Peiyu Chen Rong Zeng 《Global Energy Interconnection》 2019年第4期300-309,共10页
Traditional seawater desalination requires high amounts of energy, with correspondingly high costs and limited benefits, hindering wider applications of the process. To further improve the comprehensive economic benef... Traditional seawater desalination requires high amounts of energy, with correspondingly high costs and limited benefits, hindering wider applications of the process. To further improve the comprehensive economic benefits of seawater desalination, the desalination load can be combined with renewable energy sources such as solar energy, wind energy, and ocean energy or with the power grid to ensure its effective regulation. Utilizing energy internet(EI) technology, energy balance demand of the regional power grid, and coordinated control between coastal multi-source multi-load and regional distribution network with desalination load is reviewed herein. Several key technologies, including coordinated control of coastal multi-source multi-load system with seawater desalination load, flexible interaction between seawater desalination and regional distribution network, and combined control of coastal multi-source multi-load storage system with seawater desalination load, are discussed in detail. Adoption of the flexible interaction between seawater desalination and regional distribution networks is beneficial for solving water resource problems, improving the ability to dissipate distributed renewable energy, balancing and increasing grid loads, improving the safety and economy of coastal power grids, and achieving coordinated and comprehensive application of power grids, renewable energy sources, and coastal loads. 展开更多
关键词 DESALINATION Distribution network Power grids multi-source multi-load COORDINATED control
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Cycle-by-Cycle Queue Length Estimation for Signalized Intersections Using Multi-Source Data 被引量:4
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作者 Zhongyu Wang Qing Cai +2 位作者 Bing Wu Yinhai Wang Linbo Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第2期86-93,共8页
In order to estimate vehicular queue length at signalized intersections accurately and overcome the shortcomings and restrictions of existing studies especially those based on shockwave theory,a new methodology is pre... In order to estimate vehicular queue length at signalized intersections accurately and overcome the shortcomings and restrictions of existing studies especially those based on shockwave theory,a new methodology is presented for estimating vehicular queue length using data from both point detectors and probe vehicles. The methodology applies the shockwave theory to model queue evolution over time and space. Using probe vehicle locations and times as well as point detector measured traffic states,analytical formulations for calculating the maximum and minimum( residual) queue length are developed. The proposed methodology is verified using ground truth data collected from numerical experiments conducted in Shanghai,China. It is found that the methodology has a mean absolute percentage error of 17. 09%,which is reasonably effective in estimating the queue length at traffic signalized intersections. Limitations of the proposed models and algorithms are also discussed in the paper. 展开更多
关键词 QUEUE LENGTH estimation multi-source data TRAFFIC SIGNALS TRAFFIC SHOCKWAVE theory
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Study on the multi-sources of ore-forming materials and ore-forming fluids in the Huize lead-zinc ore deposit 被引量:4
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作者 张振亮 黄智龙 +2 位作者 管涛 严再飞 高德荣 《Chinese Journal Of Geochemistry》 EI CAS 2005年第3期243-252,共10页
The Huize large-sized Pb-Zn deposit in Yunnan Province, China, is characterized by favorable metallogenic background and particular geological settings. This suggested that the ore-forming mechanism is relatively uniq... The Huize large-sized Pb-Zn deposit in Yunnan Province, China, is characterized by favorable metallogenic background and particular geological settings. This suggested that the ore-forming mechanism is relatively unique. On the basis of geological features such as the contents of mineralization elements, the REE concentrations of gangue calcites, the REE concentrations of calcite veins in the NE-trending tectonic zone and the Pb, Sr, C, H and O isotopic compositions of different minerals, this paper presents that the ore-forming materials and ore-forming fluids of the deposit were derived from various types of strata or rocks. This is a very significant conclusion for us to further discuss the mineralization mechanism of the deposit at depth and establish an available genetic model. 展开更多
关键词 矿石 流动性 沉积作用
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Modeling the Underwater Acoustic Field Excited by an Airborne Rapidly Moving Source Using Wavenumber Integration 被引量:2
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作者 Zhang Yipeng Ma Yuanliang 《西北工业大学学报》 EI CAS CSCD 北大核心 2007年第6期855-859,共5页
It is complicated to model the acoustic field in stratified ocean for airborne aircraft,due to high speed of the source and air-to-water sound transmission.To our knowledge,there are very few papers in the open litera... It is complicated to model the acoustic field in stratified ocean for airborne aircraft,due to high speed of the source and air-to-water sound transmission.To our knowledge,there are very few papers in the open literature dealing with this complicated problem;but,in our opinion,they all require great amount of computation.We now propose a different method that requires much less computation.We improve the wavenumber integration method to model the received temporal signal for a moving source in stratified ocean and sum up in a concise form the core of our paper as follows:(A) Eq.(11) can be calculated by means of fast Chirp Z transform and the signals at all N time points are generated simultaneously;(B) direct numerical evaluation of the wavenumber integral in Eq.(4) produces large numerical errors;so it is necessary to shift the integration slightly below the real axis;(C) we compare the computation cost of direct calculation method with that of our fast calculation method;from the results presented in table 1,we can see that the fast calculation method consumes much less computation time,particularly for long duration signals;(D) for an airborne rapidly moving source,we compute the Doppler-shifted signals in shallow water and analyze their short-time Fourier transform;from Fig.1b,we can see that the received signals have multiple frequency components for a tonal source due to source motion and that each component corresponds to an arrival path. 展开更多
关键词 水下声学 空气-水声传播 快速移动资源 波数整合
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Accessing Multi-Source Geological Data through Network in MORPAS Software System 被引量:3
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作者 MeiHongbo HuGuangdao +1 位作者 ChinJian~o LiZhenhua 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期265-268,共4页
MORPAS is a special GIS (geographic information system) software system, based on the MAPGIS platform whose aim is to prospect and evaluate mineral resources quantificationally by synthesizing geological, geophysical,... MORPAS is a special GIS (geographic information system) software system, based on the MAPGIS platform whose aim is to prospect and evaluate mineral resources quantificationally by synthesizing geological, geophysical, geochemical and remote sensing data. It overlays geological database management, geological background and geological abnormality analysis, image processing of remote sensing and comprehensive abnormality analysis, etc.. It puts forward an integrative solution for the application of GIS in basic-level units and the construction of information engineering in the geological field. As the popularization of computer networks and the request of data sharing, it is necessary to extend its functions in data management so that all its data files can be accessed in the network server. This paper utilizes some MAPGIS functions for the second development and ADO (access data object) technique to access multi-source geological data in SQL Server databases. Then remote visiting and congruous management will be realized in the MORPAS system. 展开更多
关键词 multi-source geological data SQL Server accessing data through network
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