Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup compone...Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup components on the measurement results. We demonstrate that small bias shifts from the quadrature point of the modulator will induce deviation into measurement results of the two-tone system, and the simulation results correspond well to experimental and calculation results.展开更多
The article describes the possibilities of application of simulation modeling for the analysis of infrastructure and technology of transport services of enterprises. The main technological and possible economic effect...The article describes the possibilities of application of simulation modeling for the analysis of infrastructure and technology of transport services of enterprises. The main technological and possible economic effects for the enterprises arising at performance of modeling of a transport component of their work are resulted.展开更多
SARP Workshop on risk analysis of agroecological zonation and optimization of crop rotation was held at CNRRI’s research center on 24—27 Oct, 1995. Experts from Philippines, India, China, and IRRI were present in th...SARP Workshop on risk analysis of agroecological zonation and optimization of crop rotation was held at CNRRI’s research center on 24—27 Oct, 1995. Experts from Philippines, India, China, and IRRI were present in the workshop. Participants exchanged the research results on the field of land use, soil erosion. optimization of rice—wheat, rice—peanut, rice—corn cropping system in the different environments, risk analysis of rice based cropping system, nitrogen balance in rice based cropping system with system approach, demonstrated models used in their studies, and discussed the ongoing cooperative research.展开更多
One of the main objectives of artificial intelligence lies in the simulation of the behavior of living organisms;emotions are a fundamental part of life, and they cannot be left aside when simulating behavior. In this...One of the main objectives of artificial intelligence lies in the simulation of the behavior of living organisms;emotions are a fundamental part of life, and they cannot be left aside when simulating behavior. In this research, software is developed that simulates the behavior of birds with different characteristics. The latter interacts by considering different stimuli from the environment (external), and the internal state of the subject (objectives). To achieve this, a model of birds in the role of prey and predators is developed that focuses on the study of the interaction between these organisms that exhibit specific behaviors in their environment. This project is a seminal work that aims to represent the emotions of birds, and the latter caused by stimuli from a dynamic environment.展开更多
With the initiation of the National Virtual Simulation Experimental Teaching Project in 2018,educational institutions in China have recognized the significance of virtual simulation technology in reforming traditional...With the initiation of the National Virtual Simulation Experimental Teaching Project in 2018,educational institutions in China have recognized the significance of virtual simulation technology in reforming traditional teaching methods and fostering innovative talent cultivation models.Within the realm of higher education in China,motivating students to sustain their utilization of Virtual Simulation Learning Systems(VSLSs)has become a significant challenge.This article builds upon an assessment of the development status of VSLSs in Chinese higher education and draws upon previous studies to construct a model comprising three dimensions:perceived quality,perceived value,and social influence,with the aim of predicting students’enduring willingness to engage with VSLSs.To achieve this objective,a structural modeling analysis approach is employed to explore the interrelationships among the constructs under investigation,while a survey questionnaire is utilized to collect relevant data.The sample population consists of 274 college students from diverse disciplinary fields in China,including Science,Technology,Engineering,and Mathematics(STEM)and Humanities,Arts,and Social Sciences(HASS).The findings reveal that perceived value significantly influences students’willingness to participate,with perceived benefits exerting a greater impact than perceived costs.Furthermore,the overall quality of the VSLSs,encompassing aspects such as software quality,instructional design quality,and virtual simulation quality,holds substantial influence over students’perceived value.Additionally,societal factors such as course scheduling and recommendations from teachers exhibit a positive impact on students’intention to continue using VSLSs.Building upon these findings,the article presents relevant recommendations aimed at enhancing students’sustained utilization of VSLSs.展开更多
A coupled numerical method for the direct numerical simulation of particle-fluid systems is formulated and implemented, resolving an order of magnitude smaller than particle size. The particle motion is described by t...A coupled numerical method for the direct numerical simulation of particle-fluid systems is formulated and implemented, resolving an order of magnitude smaller than particle size. The particle motion is described by the time-driven hard-sphere model, while the hydrodynamic equations governing fluid flow are solved by the lattice Boltzmann method (LBM), Particle-fluid coupling is realized by an immersed boundary method (IBM), which considers the effect of boundary on surrounding fluid as a restoring force added to the governing equations of the fluid. The proposed scheme is validated in the classical flow-around-cylinder simulations, and preliminary application of this scheme to fluidization is reported, demonstrating it to be a promising computational strategy for better understanding complex behavior in particle-fluid systems.展开更多
Modelling the impact of climate change on cropping systems is crucial to support policy-making for farmers and stakeholders.Nevertheless,there exists inherent uncertainty in such cases.General Circulation Models(GCMs)...Modelling the impact of climate change on cropping systems is crucial to support policy-making for farmers and stakeholders.Nevertheless,there exists inherent uncertainty in such cases.General Circulation Models(GCMs)and future climate change scenarios(different Representative Concentration Pathways(RCPs)in different future time periods)are among the major sources of uncertainty in projecting the impact of climate change on crop grain yield.This study quantified the different sources of uncertainty associated with future climate change impact on wheat grain yield in dryland environments(Shiraz,Hamedan,Sanandaj,Kermanshah and Khorramabad)in eastern and southern Iran.These five representative locations can be categorized into three climate classes:arid cold(Shiraz),semi-arid cold(Hamedan and Sanandaj)and semi-arid cool(Kermanshah and Khorramabad).Accordingly,the downscaled daily outputs of 29 GCMs under two RCPs(RCP4.5 and RCP8.5)in the near future(2030s),middle future(2050s)and far future(2080s)were used as inputs for the Agricultural Production Systems sIMulator(APSIM)-wheat model.Analysis of variance(ANOVA)was employed to quantify the sources of uncertainty in projecting the impact of climate change on wheat grain yield.Years from 1980 to 2009 were regarded as the baseline period.The projection results indicated that wheat grain yield was expected to increase by 12.30%,17.10%,and 17.70%in the near future(2030s),middle future(2050s)and far future(2080s),respectively.The increases differed under different RCPs in different future time periods,ranging from 11.70%(under RCP4.5 in the 2030s)to 20.20%(under RCP8.5 in the 2080s)by averaging all GCMs and locations,implying that future wheat grain yield depended largely upon the rising CO2 concentrations.ANOVA results revealed that more than 97.22% of the variance in future wheat grain yield was explained by locations,followed by scenarios,GCMs,and their interactions.Specifically,at the semi-arid climate locations(Hamedan,Sanandaj,Kermanshah and Khorramabad),most of the variations arose from the scenarios(77.25%),while at the arid climate location(Shiraz),GCMs(54.00%)accounted for the greatest variation.Overall,the ensemble use of a wide range of GCMs should be given priority to narrow the uncertainty when projecting wheat grain yield under changing climate conditions,particularly in dryland environments characterized by large fluctuations in rainfall and temperature.Moreover,the current research suggested some GCMs(e.g.,the IPSL-CM5B-LR,CCSM4,and BNU-ESM)that made moderate effects in projecting the impact of climate change on wheat grain yield to be used to project future climate conditions in similar environments worldwide.展开更多
We perform numerical simulations to study the secular orbital evolution and dynamical structure of the quintuplet planetary system 55 Cancri with the self-consistent orbital solutions by Fischer and coworkers. In the ...We perform numerical simulations to study the secular orbital evolution and dynamical structure of the quintuplet planetary system 55 Cancri with the self-consistent orbital solutions by Fischer and coworkers. In the simulations, we show that this system can be stable for at least 108 yr. In addition, we extensively investigate the planetary configuration of four outer companions with one terrestrial planet in the wide region of 0.790AU 〈 a 〈 5.900AU to examine the existence of potential asteroid structure and Habitable Zones (HZs). We show that there are unstable regions for orbits about 4:1, 3:1 and 5:2 mean motion resonances (MMRs) of the outermost planet in the system, and several stable orbits can remain at 3:2 and 1:1 MMRs, which resembles the asteroid belt in the solar system. From a dynamical viewpoint, proper HZ candidates for the existence of more potential terrestrial planets reside in the wide area between 1.0 AU and 2.3 AU with relatively low eccentricities.展开更多
In order to realize reliable and fast simulation of FWM power evaluation, USSD (Uniform Step-Size Distribution) method is modified and its corresponding simulation results of FWM efficiency and computational time are ...In order to realize reliable and fast simulation of FWM power evaluation, USSD (Uniform Step-Size Distribution) method is modified and its corresponding simulation results of FWM efficiency and computational time are presented.展开更多
Cities are complex systems that develop under complicated interactions among their human and environmental components.Urbanization generates substantial outcomes and opportunities while raising challenges including co...Cities are complex systems that develop under complicated interactions among their human and environmental components.Urbanization generates substantial outcomes and opportunities while raising challenges including congestion,air pollution,inequality,etc.,calling for efficient and reasonable solutions to sustainable developments.Fortunately,booming technologies generate large-scale data of complex cities,providing a chance to propose data-driven solutions for sustainable urban developments.This paper provides a comprehensive overview of data-driven urban sustainability practice.In this review article,we conceptualize MetaCity,a general framework for optimizing resource usage and allocation problems in complex cities with data-driven approaches.Under this framework,we decompose specific urban sustainable goals,e.g.,efficiency and resilience,review practical urban problems under these goals,and explore the probability of using data-driven technologies as potential solutions to the challenge of complexity.On the basis of extensive urban data,we integrate urban problem discovery,operation of urban systems simulation,and complex decision-making problem solving into an entire cohesive framework to achieve sustainable development goals by optimizing resource allocation problems in complex cities.展开更多
Call centers have grown world-wide during the past decade. One of the most important aspects considered by call center managers is the optimization of its operators, which implies covering the highly variable demand a...Call centers have grown world-wide during the past decade. One of the most important aspects considered by call center managers is the optimization of its operators, which implies covering the highly variable demand and f'mding an efficient way to assign people to certain shifts in order to achieve a desirable service level and abandonment rate. Another challenge is determining which system setup is appropriate for the specific call center. Should we have a single-skill call center or multi-skill call center? If we do have the latter, how many multi-skill agents should we have on staff?. In this case study, we generate and analyze discrete-event systems simulation-optimization models to test the behavior of a real-world call center under the actual configuration and under different levels of cross-training. The model results help call center managers by: 1) determining the optimal number of operators needed for different staff configtmations in order to achieve the targets for service level and abandonment; 2) providing information about the trade-off between the key measurements in the call center; and 3) providing useful information about the number of operators needed and used for each hour of operation to estimate the number of four-hour shifts required to achieve the performance targets. Our experimental f'mdings from this case study suggest that a bi-skill call center is economically better in the long-rtm compared to a full-skill or single-skill call center. This case study augments the call center body of knowledge by providing additional managerial insights for the operations management community.展开更多
Using a quantum computer to simulate fermionic systems requires fermion-to-qubit transformations.Usually,lower Pauli weight of transformations means shallower quantum circuits.Therefore,most existing transformations a...Using a quantum computer to simulate fermionic systems requires fermion-to-qubit transformations.Usually,lower Pauli weight of transformations means shallower quantum circuits.Therefore,most existing transformations aim for lower Pauli weight.However,in some cases,the circuit depth depends not only on the Pauli weight but also on the coefficients of the Hamiltonian terms.In order to characterize the circuit depth of these algorithms,we propose a new metric called weighted Pauli weight,which depends on Pauli weight and coefficients of Hamiltonian terms.To achieve smaller weighted Pauli weight,we introduce a novel transformation,Huffman-code-based ternary tree(HTT)transformation,which is built upon the classical Huffman code and tailored to different Hamiltonians.We tested various molecular Hamiltonians and the results show that the weighted Pauli weight of the HTT transformation is smaller than that of commonly used mappings.At the same time,the HTT transformation also maintains a relatively small Pauli weight.The mapping we designed reduces the circuit depth of certain Hamiltonian simulation algorithms,facilitating faster simulation of fermionic systems.展开更多
The instability of the thermocapillary flow in liquid layers is studied in the present paper using the linear stability analysis.Based on the two-dimensional steady flow state,the three-dimensional disturbance with a ...The instability of the thermocapillary flow in liquid layers is studied in the present paper using the linear stability analysis.Based on the two-dimensional steady flow state,the three-dimensional disturbance with a wave number in the spanwise direction is considered.The effects of the aspect ratio and free surface shape of the liquid layer on the flow instability are studied,and the results are compared with the case with the two-dimensional disturbance.展开更多
Intelligent speed adaptation (ISA) is considered as an effective measure to reduce number of traffic accidents in the field of intelligent transportation systems (ITS). On the other hand, its effects for traffic s...Intelligent speed adaptation (ISA) is considered as an effective measure to reduce number of traffic accidents in the field of intelligent transportation systems (ITS). On the other hand, its effects for traffic safety are still doubted by many people. To make the possibility analysis, an experiment is conducted by using driving simulator. Regarding ISA ap- proaches, there are three modes: mandatory, voluntary and advisory. Among them, the advisory type seems to be the easiest one to introduce. Therefore, we focus on the advisory mode in this study by considering ISA just at the beginning stage in Japan. The experiment consists of four steps: without ISA, ISA using pictures, ISA using voices and again without ISA. The outputs obtained from the driving simulator are analyzed combined with the consciousness of the participants. The experiment shows that the ISA can improve recognition of speed limitation especially for people who have random rambling or looking aside tendency. Furthermore, the ISA especially when using voices can contribute in changing the consciousness of people who are aggressive in driving. Their driving speeds can reduce so that positive effects on traffic safety can be concluded.展开更多
As the world's largest potato producer,China plays a crucial role in global food security.However,the impacts of climate change on both the potential planting regions and climatic suitability of potato cultivation...As the world's largest potato producer,China plays a crucial role in global food security.However,the impacts of climate change on both the potential planting regions and climatic suitability of potato cultivation in China remain poorly quantified.In this study,potato planting zones were delineated based on the thermal requirements of potato,utilizing the temperature data from 2177 meteorological sites during 1961-2020.A comprehensive climatic suitability index(CCSI)was developed by integrating temperature,light,and precipitation suitability indices,weighted through Agricultural Production Systems Simulator(APSIM)-Potato model simulation.During 1991-2020,compared to 1961-1990,the unsuitable and single-season planting regions decreased by 18%and 8%,while the multiseason and winter planting regions expanded by 93%and 6%,respectively.During 1961-2020,the CCSI was highest in single-season planting regions(e.g.,Northeast China and the north agro-pastoral ecotone),followed by multi-season and winter planting regions.During 1991-2020,compared to 1961-1990,CCSI of potato planting in the singleseason planting region showed a slight decrease,but it increased by 1%-2%in the multi-season and winter planting regions.These findings demonstrate that the increase in potato climate suitability supports the expansion of potato planting area and implementation of the“Potato as Staple Food”policy.Increased precipitation and temperature identify Northwest and Southwest China as the potential expansion regions for potato planting.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 61574019,61674018 and 61674020the Fund of State Key Laboratory of Information Photonics and Optical Communicationsthe Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No 20130005130001
文摘Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup components on the measurement results. We demonstrate that small bias shifts from the quadrature point of the modulator will induce deviation into measurement results of the two-tone system, and the simulation results correspond well to experimental and calculation results.
文摘The article describes the possibilities of application of simulation modeling for the analysis of infrastructure and technology of transport services of enterprises. The main technological and possible economic effects for the enterprises arising at performance of modeling of a transport component of their work are resulted.
文摘SARP Workshop on risk analysis of agroecological zonation and optimization of crop rotation was held at CNRRI’s research center on 24—27 Oct, 1995. Experts from Philippines, India, China, and IRRI were present in the workshop. Participants exchanged the research results on the field of land use, soil erosion. optimization of rice—wheat, rice—peanut, rice—corn cropping system in the different environments, risk analysis of rice based cropping system, nitrogen balance in rice based cropping system with system approach, demonstrated models used in their studies, and discussed the ongoing cooperative research.
文摘One of the main objectives of artificial intelligence lies in the simulation of the behavior of living organisms;emotions are a fundamental part of life, and they cannot be left aside when simulating behavior. In this research, software is developed that simulates the behavior of birds with different characteristics. The latter interacts by considering different stimuli from the environment (external), and the internal state of the subject (objectives). To achieve this, a model of birds in the role of prey and predators is developed that focuses on the study of the interaction between these organisms that exhibit specific behaviors in their environment. This project is a seminal work that aims to represent the emotions of birds, and the latter caused by stimuli from a dynamic environment.
基金the National Social Sciences Found of China’s Major Program“Research on Virtual Reality Media Narrative”(No.21&ZD326).
文摘With the initiation of the National Virtual Simulation Experimental Teaching Project in 2018,educational institutions in China have recognized the significance of virtual simulation technology in reforming traditional teaching methods and fostering innovative talent cultivation models.Within the realm of higher education in China,motivating students to sustain their utilization of Virtual Simulation Learning Systems(VSLSs)has become a significant challenge.This article builds upon an assessment of the development status of VSLSs in Chinese higher education and draws upon previous studies to construct a model comprising three dimensions:perceived quality,perceived value,and social influence,with the aim of predicting students’enduring willingness to engage with VSLSs.To achieve this objective,a structural modeling analysis approach is employed to explore the interrelationships among the constructs under investigation,while a survey questionnaire is utilized to collect relevant data.The sample population consists of 274 college students from diverse disciplinary fields in China,including Science,Technology,Engineering,and Mathematics(STEM)and Humanities,Arts,and Social Sciences(HASS).The findings reveal that perceived value significantly influences students’willingness to participate,with perceived benefits exerting a greater impact than perceived costs.Furthermore,the overall quality of the VSLSs,encompassing aspects such as software quality,instructional design quality,and virtual simulation quality,holds substantial influence over students’perceived value.Additionally,societal factors such as course scheduling and recommendations from teachers exhibit a positive impact on students’intention to continue using VSLSs.Building upon these findings,the article presents relevant recommendations aimed at enhancing students’sustained utilization of VSLSs.
基金sponsored by Ministry of Finance under the grant ZDYZ2008-2National Key Science and Technology Project under the grant 2008ZX05014-003-006HZthe Chinese Academy of Sciences under the grant KGCX2-YW-124
文摘A coupled numerical method for the direct numerical simulation of particle-fluid systems is formulated and implemented, resolving an order of magnitude smaller than particle size. The particle motion is described by the time-driven hard-sphere model, while the hydrodynamic equations governing fluid flow are solved by the lattice Boltzmann method (LBM), Particle-fluid coupling is realized by an immersed boundary method (IBM), which considers the effect of boundary on surrounding fluid as a restoring force added to the governing equations of the fluid. The proposed scheme is validated in the classical flow-around-cylinder simulations, and preliminary application of this scheme to fluidization is reported, demonstrating it to be a promising computational strategy for better understanding complex behavior in particle-fluid systems.
基金funded by the Deputy of Research Affairs, Lorestan University, Iran (Contract No. 1400-6-02-518-1402)
文摘Modelling the impact of climate change on cropping systems is crucial to support policy-making for farmers and stakeholders.Nevertheless,there exists inherent uncertainty in such cases.General Circulation Models(GCMs)and future climate change scenarios(different Representative Concentration Pathways(RCPs)in different future time periods)are among the major sources of uncertainty in projecting the impact of climate change on crop grain yield.This study quantified the different sources of uncertainty associated with future climate change impact on wheat grain yield in dryland environments(Shiraz,Hamedan,Sanandaj,Kermanshah and Khorramabad)in eastern and southern Iran.These five representative locations can be categorized into three climate classes:arid cold(Shiraz),semi-arid cold(Hamedan and Sanandaj)and semi-arid cool(Kermanshah and Khorramabad).Accordingly,the downscaled daily outputs of 29 GCMs under two RCPs(RCP4.5 and RCP8.5)in the near future(2030s),middle future(2050s)and far future(2080s)were used as inputs for the Agricultural Production Systems sIMulator(APSIM)-wheat model.Analysis of variance(ANOVA)was employed to quantify the sources of uncertainty in projecting the impact of climate change on wheat grain yield.Years from 1980 to 2009 were regarded as the baseline period.The projection results indicated that wheat grain yield was expected to increase by 12.30%,17.10%,and 17.70%in the near future(2030s),middle future(2050s)and far future(2080s),respectively.The increases differed under different RCPs in different future time periods,ranging from 11.70%(under RCP4.5 in the 2030s)to 20.20%(under RCP8.5 in the 2080s)by averaging all GCMs and locations,implying that future wheat grain yield depended largely upon the rising CO2 concentrations.ANOVA results revealed that more than 97.22% of the variance in future wheat grain yield was explained by locations,followed by scenarios,GCMs,and their interactions.Specifically,at the semi-arid climate locations(Hamedan,Sanandaj,Kermanshah and Khorramabad),most of the variations arose from the scenarios(77.25%),while at the arid climate location(Shiraz),GCMs(54.00%)accounted for the greatest variation.Overall,the ensemble use of a wide range of GCMs should be given priority to narrow the uncertainty when projecting wheat grain yield under changing climate conditions,particularly in dryland environments characterized by large fluctuations in rainfall and temperature.Moreover,the current research suggested some GCMs(e.g.,the IPSL-CM5B-LR,CCSM4,and BNU-ESM)that made moderate effects in projecting the impact of climate change on wheat grain yield to be used to project future climate conditions in similar environments worldwide.
基金Supported by the National Natural Science Foundation of China
文摘We perform numerical simulations to study the secular orbital evolution and dynamical structure of the quintuplet planetary system 55 Cancri with the self-consistent orbital solutions by Fischer and coworkers. In the simulations, we show that this system can be stable for at least 108 yr. In addition, we extensively investigate the planetary configuration of four outer companions with one terrestrial planet in the wide region of 0.790AU 〈 a 〈 5.900AU to examine the existence of potential asteroid structure and Habitable Zones (HZs). We show that there are unstable regions for orbits about 4:1, 3:1 and 5:2 mean motion resonances (MMRs) of the outermost planet in the system, and several stable orbits can remain at 3:2 and 1:1 MMRs, which resembles the asteroid belt in the solar system. From a dynamical viewpoint, proper HZ candidates for the existence of more potential terrestrial planets reside in the wide area between 1.0 AU and 2.3 AU with relatively low eccentricities.
文摘In order to realize reliable and fast simulation of FWM power evaluation, USSD (Uniform Step-Size Distribution) method is modified and its corresponding simulation results of FWM efficiency and computational time are presented.
基金supported by National Natural Science Foundation of China(U23B2030,62302261)the National Key Research and Development Program of China(23IAA02114).
文摘Cities are complex systems that develop under complicated interactions among their human and environmental components.Urbanization generates substantial outcomes and opportunities while raising challenges including congestion,air pollution,inequality,etc.,calling for efficient and reasonable solutions to sustainable developments.Fortunately,booming technologies generate large-scale data of complex cities,providing a chance to propose data-driven solutions for sustainable urban developments.This paper provides a comprehensive overview of data-driven urban sustainability practice.In this review article,we conceptualize MetaCity,a general framework for optimizing resource usage and allocation problems in complex cities with data-driven approaches.Under this framework,we decompose specific urban sustainable goals,e.g.,efficiency and resilience,review practical urban problems under these goals,and explore the probability of using data-driven technologies as potential solutions to the challenge of complexity.On the basis of extensive urban data,we integrate urban problem discovery,operation of urban systems simulation,and complex decision-making problem solving into an entire cohesive framework to achieve sustainable development goals by optimizing resource allocation problems in complex cities.
文摘Call centers have grown world-wide during the past decade. One of the most important aspects considered by call center managers is the optimization of its operators, which implies covering the highly variable demand and f'mding an efficient way to assign people to certain shifts in order to achieve a desirable service level and abandonment rate. Another challenge is determining which system setup is appropriate for the specific call center. Should we have a single-skill call center or multi-skill call center? If we do have the latter, how many multi-skill agents should we have on staff?. In this case study, we generate and analyze discrete-event systems simulation-optimization models to test the behavior of a real-world call center under the actual configuration and under different levels of cross-training. The model results help call center managers by: 1) determining the optimal number of operators needed for different staff configtmations in order to achieve the targets for service level and abandonment; 2) providing information about the trade-off between the key measurements in the call center; and 3) providing useful information about the number of operators needed and used for each hour of operation to estimate the number of four-hour shifts required to achieve the performance targets. Our experimental f'mdings from this case study suggest that a bi-skill call center is economically better in the long-rtm compared to a full-skill or single-skill call center. This case study augments the call center body of knowledge by providing additional managerial insights for the operations management community.
基金supported by the National Key Research and Development Program of China(Grant No.2024YFB4504101)the National Nat-ural Science Foundation of China(Grant No.22303022)the Anhui Province Innovation Plan for Science and Technology(Grant No.202423r06050002).
文摘Using a quantum computer to simulate fermionic systems requires fermion-to-qubit transformations.Usually,lower Pauli weight of transformations means shallower quantum circuits.Therefore,most existing transformations aim for lower Pauli weight.However,in some cases,the circuit depth depends not only on the Pauli weight but also on the coefficients of the Hamiltonian terms.In order to characterize the circuit depth of these algorithms,we propose a new metric called weighted Pauli weight,which depends on Pauli weight and coefficients of Hamiltonian terms.To achieve smaller weighted Pauli weight,we introduce a novel transformation,Huffman-code-based ternary tree(HTT)transformation,which is built upon the classical Huffman code and tailored to different Hamiltonians.We tested various molecular Hamiltonians and the results show that the weighted Pauli weight of the HTT transformation is smaller than that of commonly used mappings.At the same time,the HTT transformation also maintains a relatively small Pauli weight.The mapping we designed reduces the circuit depth of certain Hamiltonian simulation algorithms,facilitating faster simulation of fermionic systems.
基金supported by the National Natural Science Foundation of China (Grants No. 10872202 and 11032011)
文摘The instability of the thermocapillary flow in liquid layers is studied in the present paper using the linear stability analysis.Based on the two-dimensional steady flow state,the three-dimensional disturbance with a wave number in the spanwise direction is considered.The effects of the aspect ratio and free surface shape of the liquid layer on the flow instability are studied,and the results are compared with the case with the two-dimensional disturbance.
文摘Intelligent speed adaptation (ISA) is considered as an effective measure to reduce number of traffic accidents in the field of intelligent transportation systems (ITS). On the other hand, its effects for traffic safety are still doubted by many people. To make the possibility analysis, an experiment is conducted by using driving simulator. Regarding ISA ap- proaches, there are three modes: mandatory, voluntary and advisory. Among them, the advisory type seems to be the easiest one to introduce. Therefore, we focus on the advisory mode in this study by considering ISA just at the beginning stage in Japan. The experiment consists of four steps: without ISA, ISA using pictures, ISA using voices and again without ISA. The outputs obtained from the driving simulator are analyzed combined with the consciousness of the participants. The experiment shows that the ISA can improve recognition of speed limitation especially for people who have random rambling or looking aside tendency. Furthermore, the ISA especially when using voices can contribute in changing the consciousness of people who are aggressive in driving. Their driving speeds can reduce so that positive effects on traffic safety can be concluded.
基金Supported by the Science and Technology Program of Inner Mongolia(2025KJHZ0003)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA28060200)+2 种基金Basic Research Fund of Chinese Academy of Meteorological Sciences(CAMS)(2024Y011,2024Z001,and 2023Z014)Key Innovative Team of Agricultural Meteorology of China Meteorological Administration(CMA2024ZD02)Science and Technology Development Fund of CAMS(2024KJ010)。
文摘As the world's largest potato producer,China plays a crucial role in global food security.However,the impacts of climate change on both the potential planting regions and climatic suitability of potato cultivation in China remain poorly quantified.In this study,potato planting zones were delineated based on the thermal requirements of potato,utilizing the temperature data from 2177 meteorological sites during 1961-2020.A comprehensive climatic suitability index(CCSI)was developed by integrating temperature,light,and precipitation suitability indices,weighted through Agricultural Production Systems Simulator(APSIM)-Potato model simulation.During 1991-2020,compared to 1961-1990,the unsuitable and single-season planting regions decreased by 18%and 8%,while the multiseason and winter planting regions expanded by 93%and 6%,respectively.During 1961-2020,the CCSI was highest in single-season planting regions(e.g.,Northeast China and the north agro-pastoral ecotone),followed by multi-season and winter planting regions.During 1991-2020,compared to 1961-1990,CCSI of potato planting in the singleseason planting region showed a slight decrease,but it increased by 1%-2%in the multi-season and winter planting regions.These findings demonstrate that the increase in potato climate suitability supports the expansion of potato planting area and implementation of the“Potato as Staple Food”policy.Increased precipitation and temperature identify Northwest and Southwest China as the potential expansion regions for potato planting.