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Industrial Green Spatial Pattern Evolution of Yangtze River Economic Belt in China 被引量:3
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作者 LI Lin LIU Ying 《Chinese Geographical Science》 SCIE CSCD 2017年第4期660-672,共13页
We use the directional slacks-based measure of efficiency and inverse distance weighting method to analyze the spatial pattern evolution of the industrial green total factor productivity of 108 cities in the Yangtze R... We use the directional slacks-based measure of efficiency and inverse distance weighting method to analyze the spatial pattern evolution of the industrial green total factor productivity of 108 cities in the Yangtze River Economic Belt in 2003–2013.Results show that both the subprime mortgage crisis and ‘the new normal' had significant negative effects on productivity growth,leading to the different spatial patterns between 2003–2008 and 2009–2013.Before 2008,green poles had gathered around some capital cities and formed a tripartite pattern,which was a typical core-periphery pattern.Due to a combination of the polarization and the diffusion effects,capital cities became the growth poles and ‘core' regions,while surrounding areas became the ‘periphery'.This was mainly caused by the innate advantage of capital cities and ‘the rise of central China' strategy.After 2008,the tripartite pattern changed to a multi-poles pattern where green poles continuously and densely spread in the midstream and downstream areas.This is due to the regional difference in the leading effect of green poles.The leading effect of green poles in midstream and downstream areas has changed from polarization to diffusion,while the polarization effect still leads in the upstream area. 展开更多
关键词 Yangtze River Economic Belt industrial green total factor productivity directional slacks-based measure of efficiency inverse distance weighting spatial pattern evolution
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Scheme for Implementing Quantum Search Algorithm in a Cluster State Quantum Computer
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作者 WANG Yan-Hui ZHANG Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1487-1490,共4页
Using cluster state and single qubit measurement one can perform the one-way quantum computation. Here we give a detailed scheme for realizing a modified Grover search algorithm using measurements on cluster state. We... Using cluster state and single qubit measurement one can perform the one-way quantum computation. Here we give a detailed scheme for realizing a modified Grover search algorithm using measurements on cluster state. We give the measurement pattern for the cluster-state realization of the algorithm and estimated the number of measurement needed for its implementation. It is found that O(2^3n/^2n^2) number of single qubit measurements is required for its realization in a cluster-state quantum computer. 展开更多
关键词 cluster state long algorithm control-phase gate measurement pattern
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Method for UAV spraying pattern measurement with PLS model based spectrum analysis 被引量:2
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作者 Ruirui Zhang Yao Wen +5 位作者 Longlong Li Liping Chen Gang Xu Yanbo Huang Qing Tang Tongchuan Yi 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2020年第3期22-28,共7页
Unmanned aerial vehicle(UAV)chemical application is widely used for crop protection,and spraying pattern is one of the most important factors that influence the chemical control efficacy.A method for UAV spraying patt... Unmanned aerial vehicle(UAV)chemical application is widely used for crop protection,and spraying pattern is one of the most important factors that influence the chemical control efficacy.A method for UAV spraying pattern measurement with partial least squares(PLS)model based spectrum analysis was proposed in this study to measure the UAV spraying pattern more accurately.The method involved the steps of fluorescent tracer solution spray and its droplets collection,the spectrum on paper strip acquiring,spectrum processing and analysis,PLS modeling.In order to verify the applicability of the method and obtain the parameters of the PLS model,UAV spraying experiments were performed in the field.Then Fluorescent tracer solution was sprayed and its droplets are collected by paper strip,and the original spectrum on paper strip obtained by a spectrometer was processed by the Savitzky-Golay and standard normalized variable(SNV)method.The prediction model of coverage rate selected as the droplet deposition parameter to measure the UAV spraying pattern,was established by using PLS method.To verify the superiority of the PLS model,a traditional linear regression(LR)model of coverage rate was established simultaneously.The results demonstrate that the method with PLS model based spectrum analysis can measure the UAV spraying pattern effectively,and PLS model has a better performance of RV2=0.94 and RMSEP=0.9446 than that of the LR model. 展开更多
关键词 pattern measurement UAV spraying spectrum model coverage rate partial least squares method
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Impacts of climate change on water quantity, water salinity, food security, and socioeconomy in Egypt 被引量:2
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作者 Mohie El Din Mohamed Omar Ahmed Moustafa Ahmed Moussa Reinhard Hinkelmann 《Water Science and Engineering》 EI CAS CSCD 2021年第1期17-27,共11页
Climate change might have direct impacts on water quantity in Egypt and lead to indirect effects on Mediterranean saltwater intrusion to groundwater,which exposes agriculture to vulnerability.This study investigated i... Climate change might have direct impacts on water quantity in Egypt and lead to indirect effects on Mediterranean saltwater intrusion to groundwater,which exposes agriculture to vulnerability.This study investigated impacts of climate change on agriculture,with particular regard to food security and socioeconomy,and quantified the effectiveness of cropping pattern adaptation measures by integrating three mathematical models.The BlueM model was used for hydrological simulations of Nasser Lake under flooding scenarios to predict the water supply from the High Aswan Dam.The water and salinity balance(WB-SAL)model was adopted to estimate the water salinity in the Nile Delta.The simulated results from the BlueM and WB-SAL models were integrated with the agricultural simulation model for Egypt(ASME)to project cropping patterns,food security,and socioeconomy throughout the country.The results showed that future climate change will directly affect the total crop area;crop areas for 13 crop types;the self-sufficiency of wheat,rice,cereal,and maize supplies;and socioeconomic indicators.The proposed cropping pattern adaptation measures focus on fixing the crop areas of rice and orchards and providing half of the population with lentils,maize,onion,vegetables,milk,and meat.The adaptation measures have the potential to promote food security without causing deterioration of the socioeconomic situation.However,water availability has much more significant effects on food security and socioeconomy than cropping pattern adaptation measures do.Accordingly,the country should rationalize water use efficiency and increase water supply.©2021 Hohai University.Production and hosting by Elsevier B.V.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Climate change Water quantity SALINITY Cropping pattern adaptation measures Food security Socioeconomy
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Detonation Propagation Characteristics of Superposition Explosive Materials 被引量:1
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作者 梁开水 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2003年第1期80-82,共3页
In order to investigate detonation propagation characteristics of different charge patterns,the detonation velocities of superposition strip shaped charges made up of a detonating cord and explosives were measured by... In order to investigate detonation propagation characteristics of different charge patterns,the detonation velocities of superposition strip shaped charges made up of a detonating cord and explosives were measured by a detonation velocity measuring instrument under conditions of different ignition.The experimental results and theoretical analysis show that the maximum detonation propagation velocity depends on the explosive materials with the maximum velocity among all the explosive materials.Using detonating cord in a superposition charge can shorten detonation propagation time and improve the efficiency of explosive energy.The measurement method of detonation propagation velocity and experimental results are presented and investigated. 展开更多
关键词 explosive materials charge pattern detonation velocity measurement detonation propagation characteristics
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Simultaneous 2D in-plane deformation measurement using electronic speckle pattern interferometry with double phase modulations 被引量:1
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作者 朱云龙 Julien Vaillant +3 位作者 Guillaume Montay Manuel Fran?ois Yassine Hadjar Aurélien Bruyant 《Chinese Optics Letters》 SCIE EI CAS CSCD 2018年第7期40-44,共5页
Electronic speckle pattern interferometry(ESPI) and digital speckle pattern interferometry are wellestablished non-contact measurement methods. They have been widely used to carry out precise deformation mapping. Ho... Electronic speckle pattern interferometry(ESPI) and digital speckle pattern interferometry are wellestablished non-contact measurement methods. They have been widely used to carry out precise deformation mapping. However, the simultaneous two-dimensional(2D) or three-dimensional(3D) deformation measurements using ESPI with phase shifting usually involve complicated and slow equipment. In this Letter, we solve these issues by proposing a modified ESPI system based on double phase modulations with only one laser and one camera. In-plane normal and shear strains are obtained with good quality. This system can also be developed to measure 3D deformation, and it has the potential to carry out faster measurements with a highspeed camera. 展开更多
关键词 Simultaneous 2D in-plane deformation measurement using electronic speckle pattern interferometry with double phase modulations
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Measurement of out-of-plane deformation of curved objects with digital speckle pattern interferometry 被引量:1
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作者 Pengfei Li Ping Cai +2 位作者 Jun Long Chiyue Liu Hao Yan 《Chinese Optics Letters》 SCIE EI CAS CSCD 2018年第11期40-46,共7页
Digital speckle pattern interferometry (DSPI) is a high-precision deformation t technique for planar objects. However, for curved objects, the three-dimensional (3D) shape information is needed in order to obtain ... Digital speckle pattern interferometry (DSPI) is a high-precision deformation t technique for planar objects. However, for curved objects, the three-dimensional (3D) shape information is needed in order to obtain correct deformation measurement in DSPI. Thus, combined shape and deformation measurement techniques of DSPI have been proposed. However, the current techniques are either complex in setup or complicated in operation. Furthermore, the operations of some techniques are too slow for real-time measurement. In this work, we propose a DSPI technique for both 3D shape and out-of-plane deformation measurement. Compared with current techniques, the proposed technique is simple in both setup and operation and is capable of fast deformation measurement. Theoretical analysis and experiments are performed. For a cylinder surface with an arch height of 9 mm, the error of out-of-plane deformation measurement is less than 0.15 μm. The effectiveness of the proposed scheme is verified. 展开更多
关键词 measurement of out-of-plane deformation of curved objects with digital speckle pattern interferometry
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Online Pattern Recognition and Data Correction of PMU Data Under GPS Spoofing Attack 被引量:3
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作者 Ancheng Xue Feiyang Xu +3 位作者 Jingsong Xu Joe H.Chow Shuang Leng Tianshu Bi 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2020年第6期1240-1249,共10页
Smart grids are increasingly dependent on data with the rapid development of communication and measurement.As one of the important data sources of smart grids,phasor measurement unit(PMU)is facing the high risk from a... Smart grids are increasingly dependent on data with the rapid development of communication and measurement.As one of the important data sources of smart grids,phasor measurement unit(PMU)is facing the high risk from attacks.Compared with cyber attacks,global position system(GPS)spoofing attacks(GSAs)are easier to implement because they can be exploited by portable devices,without the need to access the physical system.Therefore,this paper proposes a novel method for pattern recognition of GSA and an additional function of the proposed method is the data correction to the phase angle difference(PAD)deviation.Specifically,this paper analyzes the effect of GSA on PMU measurement and gives two common patterns of GSA,i.e.,the step attack and the ramp attack.Then,the method of estimating the PAD deviation across a transmission line introduced by GSA is proposed,which does not require the line parameters.After obtaining the estimated PAD deviations,the pattern of GSA can be recognized by hypothesis tests and correlation coefficients according to the statistical characteristics of the estimated PAD deviations.Finally,with the case studies,the effectiveness of the proposed method is demonstrated,and the success rate of the pattern recognition and the online performance of the proposed method are analyzed. 展开更多
关键词 global position system(GPS) GPS spoofing attack(GSA) phasor measurement pattern recognition data correction line parameter
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