Ground vibration, as the most critical public hazard of blasting, has received much attention from the community. Many countries established national standards to suppress vibration impact on structures, but a world-a...Ground vibration, as the most critical public hazard of blasting, has received much attention from the community. Many countries established national standards to suppress vibration impact on structures, but a world-accepted blasting vibration criterion on human safety is still missing. In order to evaluate human response to the vibration from blasting excavation of a large-scale rock slope in China, this study aims to suggest a revised criterion. The vibration frequency was introduced to improve the existing single-factor(peak particle velocity) standard recommended by the United States Bureau of Mines(USBM). The feasibility of the new criterion was checked based on field vibration monitoring and investigation of human reactions. Moreover, the air overpressure or blast effects on human beings have also been discussed. The result indicates that the entire zone of influence can be divided into three subzones: severe-annoyance, light-annoyance and perception zone according to the revised safety standard. Both the construction company and local residents have provided positive comments on this influence degree assessment, which indicates that the presented criterion is suitable for evaluating human response to nearby blasts. Nevertheless, this specific criterion needs more field tests and verifications before it can展开更多
Some color centers in diamond can serve as quantum bits which can be manipulated with microwave pulses and read out with laser,even at room temperature.However,the photon collection efficiency of bulk diamond is great...Some color centers in diamond can serve as quantum bits which can be manipulated with microwave pulses and read out with laser,even at room temperature.However,the photon collection efficiency of bulk diamond is greatly reduced by refraction at the diamond/air interface.To address this issue,we fabricated arrays of diamond nanostructures,differing in both diameter and top end shape,with HSQ and Cr as the etching mask materials,aiming toward large scale fabrication of single-photon sources with enhanced collection efficiency made of nitrogen vacancy(NV) embedded diamond.With a mixture of O_2 and CHF_3 gas plasma,diamond pillars with diameters down to 45 nm were obtained.The top end shape evolution has been represented with a simple model.The tests of size dependent single-photon properties confirmed an improved single-photon collection efficiency enhancement,larger than tenfold,and a mild decrease of decoherence time with decreasing pillar diameter was observed as expected.These results provide useful information for future applications of nanostructured diamond as a single-photon source.展开更多
It is a challenging topic to develop an efficient algorithm for large scale classification problems in many applications of machine learning. In this paper, a hierarchical clustering and fixed-layer local learning (HC...It is a challenging topic to develop an efficient algorithm for large scale classification problems in many applications of machine learning. In this paper, a hierarchical clustering and fixed-layer local learning (HCFLL) based support vector machine(SVM) algorithm is proposed to deal with this problem. Firstly, HCFLL hierarchically clusters a given dataset into a modified clustering feature tree based on the ideas of unsupervised clustering and supervised clustering. Then it locally trains SVM on each labeled subtree at a fixed-layer of the tree. The experimental results show that compared with the existing popular algorithms such as core vector machine and decision-tree support vector machine, HCFLL can significantly improve the training and testing speeds with comparable testing accuracy.展开更多
ZTE Corporation announced that it has completed the Inter-Operability Test (IOT)of its 3GPP R7-basedHSPA+ MIMO solution,conducted in conjunction with mainstream terminal chip platform vendors,in July 2009.
Loads in large scale industrial enterprises are always various and complex, causing insecure power quality. Meanwhile, some sensitive loads or precise instruments demand for high power quality. When voltage flicker or...Loads in large scale industrial enterprises are always various and complex, causing insecure power quality. Meanwhile, some sensitive loads or precise instruments demand for high power quality. When voltage flicker or harmonics occurs, dynamic voltage restorer (DVR) can be used to stabilize the load-side voltage, which is a good manner of improving power quality. The paper explains the load demand in large scale industrial enterprises, analyzes several common voltage compensation scheme of DVR, and comes up with another voltage compensation scheme of DVR applied for double power supply with double load. A Simulink model according to the new scheme is also built in MATLAB/Simulink to test its performance. Simulation results show that the proposed scheme can guarantee the load-side voltage stability, which is an effective scheme for managing power quality.展开更多
Guest Editor in Chief:Professor Xiao-Ping Zhang, University of Birmingham The potential for renewable energy to make contributions to mitigating the impact of climate change is expected to increase significantly in th...Guest Editor in Chief:Professor Xiao-Ping Zhang, University of Birmingham The potential for renewable energy to make contributions to mitigating the impact of climate change is expected to increase significantly in the longer term. Renewable energy generation technologies including onshore wind, offshore wind, wave,tidal, marine current, and ocean thermal energy generation as well as PV power generation, which are considered展开更多
A very large scale wind turbine can be made as a circular large scale stator frame;the frame,which can reach some kilometers in diameter and some hundred meters in height,contains many circular sail trains.The stator ...A very large scale wind turbine can be made as a circular large scale stator frame;the frame,which can reach some kilometers in diameter and some hundred meters in height,contains many circular sail trains.The stator frame can be made using a light-weight tubular design.Wind can almost freely blow through this frame.Train rails are fixed at the outer surface of the frame as horizontal rings.The distance between the rails of one ring can be made to be several meters.As a result,the number of the rings can be ten or more.Each rail ring supports one sail train that is moved with wind power around the frame.The energy of this movement is transformed to electric power and is transmitted to the base of the frame.This design can be realized in a very large scale,which is difficult to achieve using a traditional three-blade turbine.展开更多
This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method fo...This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method for the discussed problem is proposed.First,we consider the problem of quadratic optimal(QO)approximation associated with the current feasible iteration point,and we split the QO into two small-scale QOs which can be solved in parallel.Second,a feasible descent direction for the problem is obtained and a new SQO-type method is proposed,namely,splitting feasible SQO(SF-SQO)method.Moreover,under suitable conditions,we analyse the global convergence,strong convergence and rate of superlinear convergence of the SF-SQO method.Finally,preliminary numerical experiments regarding the economic dispatch of a power system are carried out,and these show that the SF-SQO method is promising.展开更多
Red emissive carbon dots(CDs)powder was synthesized on a large scale from phloroglucinol and boric acid by a novel solid state reaction with yield up to 75%.This method is safe and convenient,for it needs neither high...Red emissive carbon dots(CDs)powder was synthesized on a large scale from phloroglucinol and boric acid by a novel solid state reaction with yield up to 75%.This method is safe and convenient,for it needs neither high pressure reactors nor complicated post-treatment procedures.The as-prepared carbon dots powder exhibited strong red fluorescence with excitation-independent behavior.XPS measurement and PL spectra suggest that such red fluorescence arise from boron-doped structures in CDs,which increases along with the boron concentration on CDs surface but decreases when the concentration quenching effect takes place.To overcome the aggregation induced fluorescence quenching of the solid CDs powder,the conventional methods are dispersing CDs into a large amount of inert substrates.But our present work provides a new strategy to realize strong red fluorescence of CDs in solid state.As a result,such carbon dots powder works well for latent fingerprint identification on various material surfaces.展开更多
The tension between the Hubble constant values obtained from local measurements and cosmic microwave background(CMB)measurements has motivated us to consider the cosmological model beyondΛCDM.We investigate the cosmo...The tension between the Hubble constant values obtained from local measurements and cosmic microwave background(CMB)measurements has motivated us to consider the cosmological model beyondΛCDM.We investigate the cosmology in the large scale Lorentz violation model with a non-vanishing spatial curvature.The degeneracy among spatial curvature,cosmological constant,and cosmological contortion distribution makes the model viable in describing the known observational data.We obtain some constraints on the spatial curvature by comparing the relationship between measured distance modulus and red-shift with the predicted one,the evolution of matter density over time,and the evolution of effective cosmological constant.The implications of the large scale Lorentz violation model with the non-vanishing spatial curvature under these constrains are discussed.展开更多
A simplified group search optimizer algorithm denoted as"SGSO"for large scale global optimization is presented in this paper to obtain a simple algorithm with superior performance on high-dimensional problem...A simplified group search optimizer algorithm denoted as"SGSO"for large scale global optimization is presented in this paper to obtain a simple algorithm with superior performance on high-dimensional problems.The SGSO adopts an improved sharing strategy which shares information of not only the best member but also the other good members,and uses a simpler search method instead of searching by the head angle.Furthermore,the SGSO increases the percentage of scroungers to accelerate convergence speed.Compared with genetic algorithm(GA),particle swarm optimizer(PSO)and group search optimizer(GSO),SGSO is tested on seven benchmark functions with dimensions 30,100,500 and 1 000.It can be concluded that the SGSO has a remarkably superior performance to GA,PSO and GSO for large scale global optimization.展开更多
In this paper,we consider the periodic solution problems for the systems withunbounded delay,and the existence,uniqueness and stability of the periodic solution are dealtwith unitedly.First we establish the suitable d...In this paper,we consider the periodic solution problems for the systems withunbounded delay,and the existence,uniqueness and stability of the periodic solution are dealtwith unitedly.First we establish the suitable delay-differential inequality,then study seperatelythe problems of periodic solution for the systems with bounded delay,with unbounded delayand the Volterra integral-dlfferentlal systems with infinite delay by using the character of matrixmeasure and the asymptotic fixed point theorem of poincaré’s periodic operator in the differentphase spaces.A series of simple criteria for the existence,uniqueness and stability of thesesystems are obtained.展开更多
Graph partition is a classical combinatorial optimization and graph theory problem,and it has a lot of applications,such as scientific computing,VLSI design and clustering etc.In this paper,we study the partition prob...Graph partition is a classical combinatorial optimization and graph theory problem,and it has a lot of applications,such as scientific computing,VLSI design and clustering etc.In this paper,we study the partition problem on large scale directed graphs under a new objective function,a new instance of graph partition problem.We firstly propose the modeling of this problem,then design an algorithm based on multi-level strategy and recursive partition method,and finally do a lot of simulation experiments.The experimental results verify the stability of our algorithm and show that our algorithm has the same good performance as METIS.In addition,our algorithm is better than METIS on unbalanced ratio.展开更多
The "Large Scale Scientific Computation (LSSC) Research"project is one of the State Major Basic Research projects funded by the Chinese Ministry of Science and Technology in the field ofinformation scien... The "Large Scale Scientific Computation (LSSC) Research"project is one of the State Major Basic Research projects funded by the Chinese Ministry of Science and Technology in the field ofinformation science and technology.……展开更多
The main constituent parts of unmanned aerial vehicle aerial photogrammetry systems are discussed.The key issues including the division of regional networks,the layout of regional networks,the correction of lens disto...The main constituent parts of unmanned aerial vehicle aerial photogrammetry systems are discussed.The key issues including the division of regional networks,the layout of regional networks,the correction of lens distortion,the optimization of external orientation elements,the aerial triangulation,the image matching and fusion,and the production of digital elevation models and digital orthoimages,tilt real 3 D models,and digital line drawings,were analyzed.The advantages of UAV aerial photogrammetry were compared.This study provides reference for measuring large-scale topographic maps by UAV photogrammetry systems.展开更多
Based on relevant urban planning and design standards and a study on successful cases of comprehensive urban design in China, this paper explores a methodology of comprehensive urban design in large scale projects by ...Based on relevant urban planning and design standards and a study on successful cases of comprehensive urban design in China, this paper explores a methodology of comprehensive urban design in large scale projects by applying classical urban design theories and advanced digital technologies. This enables a combination of artful design and scientifi c analysis through the establishment of an urban design indicator system, the application of digital technologies and a multi-leveled control over design contents. The chosen case of the Daqing Comprehensive Urban Design shows that the proposed measures can effectively promote the supervision of comprehensive urban design on both urban morphology and landscape, rapidly convert the urban design outcomes into management rules, and ultimately facilitate the application of the urban design outcomes.展开更多
Although it is generally understood that change is a fundamental component of managing projects in the construction industry in general and an inevitable challenge for large scale infrastructure project in particular,...Although it is generally understood that change is a fundamental component of managing projects in the construction industry in general and an inevitable challenge for large scale infrastructure project in particular, there has been little to no attention in the literature to understand change in this context from a more holistic perspective. For this purpose, this work looks at change through the eyes of a framework of six batteries of change that seem essential to charge an organization's capabilities for change. The framework brings together the expertise of four specialists that all have developed their insights over many years of study and practice, and has been validated through an extensive review of the management literature on organization development and change. Reflections on the application of this model in the construction industry and in large scale infrastructure projects demonstrate that energizing organizations to successfully deal with change goes beyond the traditional techniques of managing change from a program or project management perspective. Assessing the six batteries of change in this context can help organizations to develop capabilities for change that build change energy by balancing formal/rational methods with informal/emotional interventions at both a local(department/subproject) and global(business) level.展开更多
Late June in China is the time of year when the national college entrance examination results are announced and the whole country is whipped into a frenzy. Because of the competition and pressure on students for top u...Late June in China is the time of year when the national college entrance examination results are announced and the whole country is whipped into a frenzy. Because of the competition and pressure on students for top university openings, those who score展开更多
基金the Chinese National Programs for Fundamental Research and Development(973 Program)under Grant No.2011CB013501the Chinese National Science Fund for Distinguished Young Scholars under Grant No.51125037the Chinese National Natural Science Foundation under Grant Nos.51179138,51279135,51279146 and 51009013
文摘Ground vibration, as the most critical public hazard of blasting, has received much attention from the community. Many countries established national standards to suppress vibration impact on structures, but a world-accepted blasting vibration criterion on human safety is still missing. In order to evaluate human response to the vibration from blasting excavation of a large-scale rock slope in China, this study aims to suggest a revised criterion. The vibration frequency was introduced to improve the existing single-factor(peak particle velocity) standard recommended by the United States Bureau of Mines(USBM). The feasibility of the new criterion was checked based on field vibration monitoring and investigation of human reactions. Moreover, the air overpressure or blast effects on human beings have also been discussed. The result indicates that the entire zone of influence can be divided into three subzones: severe-annoyance, light-annoyance and perception zone according to the revised safety standard. Both the construction company and local residents have provided positive comments on this influence degree assessment, which indicates that the presented criterion is suitable for evaluating human response to nearby blasts. Nevertheless, this specific criterion needs more field tests and verifications before it can
基金Project supported by the National Key Research and Development Plan of China(Grant No.2016YFA0200402)the National Natural Science Foundation of China(Grants Nos.11574369,11574368,91323304,11174362,and 51272278)the FP7 Marie Curie Action(project No.295208)sponsored by the European Commission
文摘Some color centers in diamond can serve as quantum bits which can be manipulated with microwave pulses and read out with laser,even at room temperature.However,the photon collection efficiency of bulk diamond is greatly reduced by refraction at the diamond/air interface.To address this issue,we fabricated arrays of diamond nanostructures,differing in both diameter and top end shape,with HSQ and Cr as the etching mask materials,aiming toward large scale fabrication of single-photon sources with enhanced collection efficiency made of nitrogen vacancy(NV) embedded diamond.With a mixture of O_2 and CHF_3 gas plasma,diamond pillars with diameters down to 45 nm were obtained.The top end shape evolution has been represented with a simple model.The tests of size dependent single-photon properties confirmed an improved single-photon collection efficiency enhancement,larger than tenfold,and a mild decrease of decoherence time with decreasing pillar diameter was observed as expected.These results provide useful information for future applications of nanostructured diamond as a single-photon source.
基金National Natural Science Foundation of China ( No. 61070033 )Fundamental Research Funds for the Central Universities,China( No. 2012ZM0061)
文摘It is a challenging topic to develop an efficient algorithm for large scale classification problems in many applications of machine learning. In this paper, a hierarchical clustering and fixed-layer local learning (HCFLL) based support vector machine(SVM) algorithm is proposed to deal with this problem. Firstly, HCFLL hierarchically clusters a given dataset into a modified clustering feature tree based on the ideas of unsupervised clustering and supervised clustering. Then it locally trains SVM on each labeled subtree at a fixed-layer of the tree. The experimental results show that compared with the existing popular algorithms such as core vector machine and decision-tree support vector machine, HCFLL can significantly improve the training and testing speeds with comparable testing accuracy.
文摘ZTE Corporation announced that it has completed the Inter-Operability Test (IOT)of its 3GPP R7-basedHSPA+ MIMO solution,conducted in conjunction with mainstream terminal chip platform vendors,in July 2009.
文摘Loads in large scale industrial enterprises are always various and complex, causing insecure power quality. Meanwhile, some sensitive loads or precise instruments demand for high power quality. When voltage flicker or harmonics occurs, dynamic voltage restorer (DVR) can be used to stabilize the load-side voltage, which is a good manner of improving power quality. The paper explains the load demand in large scale industrial enterprises, analyzes several common voltage compensation scheme of DVR, and comes up with another voltage compensation scheme of DVR applied for double power supply with double load. A Simulink model according to the new scheme is also built in MATLAB/Simulink to test its performance. Simulation results show that the proposed scheme can guarantee the load-side voltage stability, which is an effective scheme for managing power quality.
文摘Guest Editor in Chief:Professor Xiao-Ping Zhang, University of Birmingham The potential for renewable energy to make contributions to mitigating the impact of climate change is expected to increase significantly in the longer term. Renewable energy generation technologies including onshore wind, offshore wind, wave,tidal, marine current, and ocean thermal energy generation as well as PV power generation, which are considered
文摘A very large scale wind turbine can be made as a circular large scale stator frame;the frame,which can reach some kilometers in diameter and some hundred meters in height,contains many circular sail trains.The stator frame can be made using a light-weight tubular design.Wind can almost freely blow through this frame.Train rails are fixed at the outer surface of the frame as horizontal rings.The distance between the rails of one ring can be made to be several meters.As a result,the number of the rings can be ten or more.Each rail ring supports one sail train that is moved with wind power around the frame.The energy of this movement is transformed to electric power and is transmitted to the base of the frame.This design can be realized in a very large scale,which is difficult to achieve using a traditional three-blade turbine.
基金supported by the National Natural Science Foundation of China(12171106)the Natural Science Foundation of Guangxi Province(2020GXNSFDA238017 and 2018GXNSFFA281007)the Shanghai Sailing Program(21YF1430300)。
文摘This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method for the discussed problem is proposed.First,we consider the problem of quadratic optimal(QO)approximation associated with the current feasible iteration point,and we split the QO into two small-scale QOs which can be solved in parallel.Second,a feasible descent direction for the problem is obtained and a new SQO-type method is proposed,namely,splitting feasible SQO(SF-SQO)method.Moreover,under suitable conditions,we analyse the global convergence,strong convergence and rate of superlinear convergence of the SF-SQO method.Finally,preliminary numerical experiments regarding the economic dispatch of a power system are carried out,and these show that the SF-SQO method is promising.
基金financially supported by the National Natural Science Foundation of China(Nos.21975048,21771039)the Science and Technology Commission of Shanghai Municipality(No.19DZ2270100)。
文摘Red emissive carbon dots(CDs)powder was synthesized on a large scale from phloroglucinol and boric acid by a novel solid state reaction with yield up to 75%.This method is safe and convenient,for it needs neither high pressure reactors nor complicated post-treatment procedures.The as-prepared carbon dots powder exhibited strong red fluorescence with excitation-independent behavior.XPS measurement and PL spectra suggest that such red fluorescence arise from boron-doped structures in CDs,which increases along with the boron concentration on CDs surface but decreases when the concentration quenching effect takes place.To overcome the aggregation induced fluorescence quenching of the solid CDs powder,the conventional methods are dispersing CDs into a large amount of inert substrates.But our present work provides a new strategy to realize strong red fluorescence of CDs in solid state.As a result,such carbon dots powder works well for latent fingerprint identification on various material surfaces.
基金Supported by the National Natural Science Foundation of China (11775080, 11865016)。
文摘The tension between the Hubble constant values obtained from local measurements and cosmic microwave background(CMB)measurements has motivated us to consider the cosmological model beyondΛCDM.We investigate the cosmology in the large scale Lorentz violation model with a non-vanishing spatial curvature.The degeneracy among spatial curvature,cosmological constant,and cosmological contortion distribution makes the model viable in describing the known observational data.We obtain some constraints on the spatial curvature by comparing the relationship between measured distance modulus and red-shift with the predicted one,the evolution of matter density over time,and the evolution of effective cosmological constant.The implications of the large scale Lorentz violation model with the non-vanishing spatial curvature under these constrains are discussed.
基金the Science and Technology Planning Project of Hunan Province(No.2011TP4016-3)the Construct Program of the Key Discipline(Technology of Computer Application)in Xiangnan University
文摘A simplified group search optimizer algorithm denoted as"SGSO"for large scale global optimization is presented in this paper to obtain a simple algorithm with superior performance on high-dimensional problems.The SGSO adopts an improved sharing strategy which shares information of not only the best member but also the other good members,and uses a simpler search method instead of searching by the head angle.Furthermore,the SGSO increases the percentage of scroungers to accelerate convergence speed.Compared with genetic algorithm(GA),particle swarm optimizer(PSO)and group search optimizer(GSO),SGSO is tested on seven benchmark functions with dimensions 30,100,500 and 1 000.It can be concluded that the SGSO has a remarkably superior performance to GA,PSO and GSO for large scale global optimization.
文摘In this paper,we consider the periodic solution problems for the systems withunbounded delay,and the existence,uniqueness and stability of the periodic solution are dealtwith unitedly.First we establish the suitable delay-differential inequality,then study seperatelythe problems of periodic solution for the systems with bounded delay,with unbounded delayand the Volterra integral-dlfferentlal systems with infinite delay by using the character of matrixmeasure and the asymptotic fixed point theorem of poincaré’s periodic operator in the differentphase spaces.A series of simple criteria for the existence,uniqueness and stability of thesesystems are obtained.
基金supported by National Numerical Windtunnel Project(No.NNW2019ZT5-B16)National Natural Science Foundation of China(Nos.11871256,12071194)the Basic Research Project of Qinghai(No.2021-ZJ-703).
文摘Graph partition is a classical combinatorial optimization and graph theory problem,and it has a lot of applications,such as scientific computing,VLSI design and clustering etc.In this paper,we study the partition problem on large scale directed graphs under a new objective function,a new instance of graph partition problem.We firstly propose the modeling of this problem,then design an algorithm based on multi-level strategy and recursive partition method,and finally do a lot of simulation experiments.The experimental results verify the stability of our algorithm and show that our algorithm has the same good performance as METIS.In addition,our algorithm is better than METIS on unbalanced ratio.
文摘 The "Large Scale Scientific Computation (LSSC) Research"project is one of the State Major Basic Research projects funded by the Chinese Ministry of Science and Technology in the field ofinformation science and technology.……
文摘The main constituent parts of unmanned aerial vehicle aerial photogrammetry systems are discussed.The key issues including the division of regional networks,the layout of regional networks,the correction of lens distortion,the optimization of external orientation elements,the aerial triangulation,the image matching and fusion,and the production of digital elevation models and digital orthoimages,tilt real 3 D models,and digital line drawings,were analyzed.The advantages of UAV aerial photogrammetry were compared.This study provides reference for measuring large-scale topographic maps by UAV photogrammetry systems.
文摘Based on relevant urban planning and design standards and a study on successful cases of comprehensive urban design in China, this paper explores a methodology of comprehensive urban design in large scale projects by applying classical urban design theories and advanced digital technologies. This enables a combination of artful design and scientifi c analysis through the establishment of an urban design indicator system, the application of digital technologies and a multi-leveled control over design contents. The chosen case of the Daqing Comprehensive Urban Design shows that the proposed measures can effectively promote the supervision of comprehensive urban design on both urban morphology and landscape, rapidly convert the urban design outcomes into management rules, and ultimately facilitate the application of the urban design outcomes.
文摘Although it is generally understood that change is a fundamental component of managing projects in the construction industry in general and an inevitable challenge for large scale infrastructure project in particular, there has been little to no attention in the literature to understand change in this context from a more holistic perspective. For this purpose, this work looks at change through the eyes of a framework of six batteries of change that seem essential to charge an organization's capabilities for change. The framework brings together the expertise of four specialists that all have developed their insights over many years of study and practice, and has been validated through an extensive review of the management literature on organization development and change. Reflections on the application of this model in the construction industry and in large scale infrastructure projects demonstrate that energizing organizations to successfully deal with change goes beyond the traditional techniques of managing change from a program or project management perspective. Assessing the six batteries of change in this context can help organizations to develop capabilities for change that build change energy by balancing formal/rational methods with informal/emotional interventions at both a local(department/subproject) and global(business) level.
文摘Late June in China is the time of year when the national college entrance examination results are announced and the whole country is whipped into a frenzy. Because of the competition and pressure on students for top university openings, those who score
