Ladle furnaces are known for their high power consumption,making research on power-saving process crucial.In response to the defect of thin slag thickness in the industrial production of a 120-t ladle furnace at a ste...Ladle furnaces are known for their high power consumption,making research on power-saving process crucial.In response to the defect of thin slag thickness in the industrial production of a 120-t ladle furnace at a steel plant,with its production of ship plate steel DH36 as the focus,experiments involving adding the foaming agent and shifting power delivery gears were conducted.Based on the principle of measuring alternating current by Rogowski coils,the power consumption during the ladle furnace refining process was calculated theoretically,and the actual industrial power consumption matched with it basically,confirming the accuracy of the theoretical calculations.Additionally,the impacts of argon flow rate,foaming agents,and shifting power delivery gears on power consumption were studied.The results showed that adding 0.59 and 0.50 kg/t foaming agents in two batches improved the refining process of the ladle furnace,allowing for effective submerged-arc operations and saving electric energy of 7.2382 kWh per ton of steel.Similarly,utilizing a power supply mode of 7-step short arc during the refining process significantly enhanced the desulfurization rate of molten steel and saved electric energy of 11.6387 kWh per ton of steel.展开更多
Reconfigurable intelligent surfaces(RISs)with the capability of nearly passive beamforming,have recently sparked considerable interests.This paper presents an energy-efficient discrete phase encoding method for RIS-as...Reconfigurable intelligent surfaces(RISs)with the capability of nearly passive beamforming,have recently sparked considerable interests.This paper presents an energy-efficient discrete phase encoding method for RIS-assisted communication systems.Firstly,the beamforming gain,power consumption and energy efficiency models for the RIS-assisted system are illustrated.On this basis,the discrete phase encoding problem is formulated for the purpose of improving the energy efficiency,under the power constraint and the quality-of-service(QoS)requirement.According to the interrelation between the phase encoding and power consumption,a three-step encoding method is proposed with the capability of customizing the beamforming gain,power consumption,and energy efficiency.Simulation results indicate that the proposed method is capable of achieving a more favorable performance in terms of satisfying the QoS demand,reducing the power consumption,and improving the energy efficiency.Furthermore,two field trials at 35 GHz evidence the superiority performance and feasibility characteristics of the proposed method in real environment.This work may provide a reference for future applications of RIS-assisted system with an energy-efficient manner.展开更多
The rapid evolution and expanding scale of AI(artificial intelligence)technologies exert unprecedented energy demands on global electrical grids.Powering computationally intensive tasks such as large-scale AI model tr...The rapid evolution and expanding scale of AI(artificial intelligence)technologies exert unprecedented energy demands on global electrical grids.Powering computationally intensive tasks such as large-scale AI model training and widespread real-time inference necessitates substantial electricity consumption,presenting a significant challenge to conventional power infrastructure.This paper examines the critical need for a fundamental shift towards smart energy grids in response to AI’s growing energy footprint.It delves into the symbiotic relationship wherein AI acts as a significant energy consumer while offering the intelligence required for dynamic load management,efficient integration of renewable energy sources,and optimized grid operations.We posit that advanced smart grids are indispensable for facilitating AI’s sustainable growth,underscoring this synergy as a pivotal advancement toward a resilient energy future.展开更多
The intermittency and volatility of wind and photovoltaic power generation exacerbate issues such as wind and solar curtailment,hindering the efficient utilization of renewable energy and the low-carbon development of...The intermittency and volatility of wind and photovoltaic power generation exacerbate issues such as wind and solar curtailment,hindering the efficient utilization of renewable energy and the low-carbon development of energy systems.To enhance the consumption capacity of green power,the green power system consumption optimization scheduling model(GPS-COSM)is proposed,which comprehensively integrates green power system,electric boiler,combined heat and power unit,thermal energy storage,and electrical energy storage.The optimization objectives are to minimize operating cost,minimize carbon emission,and maximize the consumption of wind and solar curtailment.The multi-objective particle swarm optimization algorithm is employed to solve the model,and a fuzzy membership function is introduced to evaluate the satisfaction level of the Pareto optimal solution set,thereby selecting the optimal compromise solution to achieve a dynamic balance among economic efficiency,environmental friendliness,and energy utilization efficiency.Three typical operating modes are designed for comparative analysis.The results demonstrate that the mode involving the coordinated operation of electric boiler,thermal energy storage,and electrical energy storage performs the best in terms of economic efficiency,environmental friendliness,and renewable energy utilization efficiency,achieving the wind and solar curtailment consumption rate of 99.58%.The application of electric boiler significantly enhances the direct accommodation capacity of the green power system.Thermal energy storage optimizes intertemporal regulation,while electrical energy storage strengthens the system’s dynamic regulation capability.The coordinated optimization of multiple devices significantly reduces reliance on fossil fuels.展开更多
A 37. 5 MHz differential complementary metal oxide semiconductor （CMOS） crystal oscillator with low power and low phase noise for the radio frequency tuner of digital radio broadcasting digital radio mondiale （DRAM...A 37. 5 MHz differential complementary metal oxide semiconductor （CMOS） crystal oscillator with low power and low phase noise for the radio frequency tuner of digital radio broadcasting digital radio mondiale （DRAM） and digital audio broadcasting （DAB） systems is realized and characterized. The conventional cross-coupled n-type metal oxide semiconductor （NMOS） transistors are replaced by p-type metal oxide semiconductor （PMOS） transistors to decrease the phase noise in the core part of the crystal oscillator. A symmetry structure of the current mirror is adopted to increase the stability of direct current. The amplitude detecting circuit made up of a single- stage CMOS operational transconductance amplifier （OTA） and a simple amplitude detector is used to improve the current accuracy of the output signals. The chip is fabricated in a 0. 18- pxn CMOS process, and the total chip size is 0. 35 mm x 0. 3 mm. Under a supply voltage of 1.8 V, the measured power consumption is 3.6 mW including the output buffer for 50 testing loads. The proposed crystal oscillator exhibits a low phase noise of - 134. 7 dBc/Hz at 1-kHz offset from the center frequency of 37. 5 MHz.展开更多
The power consumption and electric field distribution in a field emission display （FED） panel is optimized with a novel pixel structure. A circuit model is proposed to estimate the total power consumption in an FED ...The power consumption and electric field distribution in a field emission display （FED） panel is optimized with a novel pixel structure. A circuit model is proposed to estimate the total power consumption in an FED panel which is composed of anode energy consumption, energy loss due to the leakage current and the energy dissipated in the parasitic capacitances. Moreover, the parasitic capacitances play a vital part in the power consumption and driving performance. In order to lower the parasitic capacitances, multiple dielectric layers are used as the gate electrode. Due to different etching speeds, a novel pixel structure is formed. As a result, the power consumption of an FED panel is reduced by 28% in a full white picture, and the electron beam performance is also better than that of the conventional structure.展开更多
Electric power consumption(EPC)is one of the basic indices for evaluating electric power use.Obtaining timely and accurate data on the spatiotemporal dynamics of EPC is crucial for understanding and practical deployme...Electric power consumption(EPC)is one of the basic indices for evaluating electric power use.Obtaining timely and accurate data on the spatiotemporal dynamics of EPC is crucial for understanding and practical deployment of electric power resources.In this study,an EPC model was developed using stable nighttime lights time-series data from the Defense Meteorological Satellite Program Operational Linescan System(DMSP/OLS).The model was used to reconstruct the spatial patterns of EPC in Chinese Mainland at the county level from 1995 to 2008.In addition,the spatiotemporal dynamics of EPC were analyzed,and the fol-lowing conclusions were drawn.(1)The EPC model reliably represented the spatiotemporal dynamics of EPC in Chinese Mainland with approximately 70%accuracy.(2)The EPC in most regions of Chinese Mainland was at low to moderate levels,with marked temporal and spatial variations;of high-level EPC,58.26%was concentrated in eastern China.Six urban agglomerations(Beijing-Tianjin-Tangshan region,Shanghai-Nanjing-Hangzhou region,Pearl River Delta,Shandong Peninsula,middle-south of Liaoning Province,and Sichuan Basin)accounted for 10.69%of the total area of Chinese Mainland but consumed 39.23%of the electricity.(3)The EPC of most regions in Chinese Mainland increased from 1995 to 2008,and 64%of the mainland area showed a significant increase in EPC.Moderate increases in EPC were found in 61.62%of eastern China and 80.65%of central China from 1995 to 2008,whereas 75.69%of western China showed no significant increase in EPC.Meanwhile,77.27%,89.35%,and 66.72%of the Shanghai-Nanjing-Hangzhou region,Pearl River Delta,and Shandong Peninsula,respectively,showed high-speed increases in EPC.Moderate increases in EPC occurred in 71.12%and 72.13%of the Beijing-Tianjin-Tangshan region and middle-south of Liaoning Province,respectively,while no significant increase occurred in 56.34%of the Sichuan Basin.展开更多
A coaxial mixer meeting the actual demand of a system with high and variable viscosity is investigated. It has an outer wall-scraping frame and a double inner impeller consisting of a four-pitched-blade turbine and Ru...A coaxial mixer meeting the actual demand of a system with high and variable viscosity is investigated. It has an outer wall-scraping frame and a double inner impeller consisting of a four-pitched-blade turbine and Rushton turbine. The power consumption and flow field characteristics of the coaxial mixer in laminar and transitional flow are simulated numerically, and then the distribution of velocity field, shear rate and mass flow rate are analyzed. The simulation results indicate that the outer frame has little effect on the power consumption of the double inner impeller whether in laminar or transitional flow, whereas the inner combined impeller has a great effect on the power consumption of the outer frame. Compared with the single rotation mode, the power consumption of the outer frame will decrease in co-rotation mode and increase in counter-rotation mode. The velocity, shear rate and mass flow rate are relatively high near the inner impeller in all operating modes, and only under double-shaft agitation will the mixing performance near the free surface be improved.In addition, these distributions in the co-rotation and counter-rotation modes show little difference, but the co-rotation mode is recommended for the advantage of low power consumption.展开更多
The role of baffles in mechanically stirred tanks is to promote the stability of power drawn by the impeller and to avoid the fluid swirling, thus enhancing mixing. The present paper numerically investigates the baffl...The role of baffles in mechanically stirred tanks is to promote the stability of power drawn by the impeller and to avoid the fluid swirling, thus enhancing mixing. The present paper numerically investigates the baffles effects in a vessel stirred by a Rushton turbine. The geometric factor of interest is the baffle inclination which is varying between 25°, 32.5°, 45°, 70° and 90° at different impeller rotational speeds. The impeller rotational direction has also been varied. The vortex size and power consumption were evaluated for each geometrical configuration. It was found that the best configuration is the baffle inclination by = 70° at a negative angular velocity.展开更多
The power consumption of a variable optical attenuator（VOA） array based on a silica planar lightwave circuit was investigated. The thermal field profile of the device was optimized using the finite-element analysis....The power consumption of a variable optical attenuator（VOA） array based on a silica planar lightwave circuit was investigated. The thermal field profile of the device was optimized using the finite-element analysis. The simulation results showed that the power consumption reduces as the depth of the heat-insulating grooves is deeper, the up-cladding is thinner,the down-cladding is thicker, and the width of the cladding ridge is narrower. The materials component and thickness of the electrodes were also optimized to guarantee the driving voltage under 5 V. The power consumption was successfully reduced to as low as 155 mW at an attenuation of 30 dB in the experiment.展开更多
Discrete element method(DEM)simulations of particle mixing process in an intensive mixer were conducted to study the influence of structural and process parameters on the mixing performance and power consumption.The D...Discrete element method(DEM)simulations of particle mixing process in an intensive mixer were conducted to study the influence of structural and process parameters on the mixing performance and power consumption.The DEM model was verified by comparing the impeller torque obtained from simulation with that from experiment.Impeller and vessel torque,coordination number(CN)and mixing index(Relative standard deviation)were adopted to qualify the particle dynamics and mixing performance with different parameters.A method based on cubic polynomial fitting was proposed to determine the critical mixing time and critical specific input work during the mixing process.It is found that the mixing performance and energy efficiency increases with the decrease of impeller offset.The mixing performance is improved slightly with the increase of blade number and the impeller with 3 blades has the highest energy efficiency due to its low input torque.Results indicate that the energy efficiency and the mixing performance increase with the decrease of filling level when the height of granular bed is higher than that of blade.展开更多
A new power estimation method is proposed for base station(BS) in this paper.Based on this method,a software platform for power estimation is developed.The proposed method models power consumption on different abstrac...A new power estimation method is proposed for base station(BS) in this paper.Based on this method,a software platform for power estimation is developed.The proposed method models power consumption on different abstraction levels by splitting a typical base station into several basic components at different levels in the view of embedded system design.In particular,our focus is on baseband IC(Integrate Circuit) due to it's the dominant power consumer in small cells.Baseband power model is based on arithmetic computing costs of selected algorithms.All computing and storage costs are calibrated using algorithm complexity,hardware architecture,activity ratio,silicon technology,and overheads on all hierarchies.Micro architecture and IC technology are considered.The model enables power comparison of different types of base stations configured with different baseband algorithms,micro architectures,and ICs.The model also supports cellular operators in power estimation of different deployment strategies and transmission schemes.The model is verified by comparing power consumption with a real LTE base station.By exposing more configuration freedoms,the platform can be used for power estimation of current and future base stations.展开更多
Using composite field arithmetic in Galois field can result in the compact Rijndael S-Box. However, the power con- sumption of this solution is too large to be used in resource-limited embedded systems. A full-custom ...Using composite field arithmetic in Galois field can result in the compact Rijndael S-Box. However, the power con- sumption of this solution is too large to be used in resource-limited embedded systems. A full-custom hardware implementation of composite field S-Box is proposed for these targeted domains in this paper. The minimization of power consumption is implemented by optimizing the architecture of the composite field S-Box and using the pass transmission gate (PTG) to realize the logic functions of S-Box. Power simulations were performed using the netlist extracted from the layout. HSPICE simulation results indicated that the proposed S-Box achieves low power consumption of about 130 μW at 10 MHz using 0.25 μm/2.5 V technology, while the consumptions of the positive polarity reed-muller (PPRM) based S-Box and composite field S-Box based on the conventional CMOS logic style are about 240 μW and 420 μW, respectively. The simulations also showed that the presented S-Box obtains better low-voltage operating property, which is clearly relevant for applications like sensor nodes, smart cards and radio frequency identification (RFID) tags.展开更多
We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. Fo...We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. For a 2-mm-long and 10-μm-wide laser coated with high-reflectivity on the rear facet, more than 170mW of output power is obtained at 20℃ with a threshold power consumption of 2.4 W, corresponding to 30mW with a threshold power consumption of 3.9 W at 90℃. Robust single-mode emission with a side-mode suppression ratio above 25 dB is continuously tunable by the heat sink temperature or injection current.展开更多
A test pattern generator （TPG） which can highly reduce the peak power consumption during built-in self-test （BIST） application is proposed. The proposed TPG, called LPpe-TPG, consists of a linear feedback shift re...A test pattern generator （TPG） which can highly reduce the peak power consumption during built-in self-test （BIST） application is proposed. The proposed TPG, called LPpe-TPG, consists of a linear feedback shift register （LFSR） and some control circuits. A procedure is presented firstly to make compare vectors between pseudorandom test patterns by adding some circuits to the original LFSR and secondly to insert some vectors between two successive pseudorandom test patterns according to the ordinal selection of every two bits of the compare vector. Then the changes between any successive test patterns of the test set generated by the LPpe-TPG are not more than twice. This leads to a decrease of the weighted switching activity （WSA） of the circuit under test （CUT） and therefore a reduction of the power consumption. Experimental results based on some ISCAS＇ 85 benchmark circuits show that the peak power consumption has been reduced by 25.25% to 64.46%. Also, the effectiveness of our approach to reduce the total and average power consumption is kept, without losing stuck-at fault coverage.展开更多
It is of great significance to reasonably distribute the slung load to each helicopter while considering difference in power consumption,relative position and interaction comprehensively.Therefore,the load distributio...It is of great significance to reasonably distribute the slung load to each helicopter while considering difference in power consumption,relative position and interaction comprehensively.Therefore,the load distribution strategy based on power consumption and robust adaptive game control is proposed in this paper.The study is on a"2-lead"multi-lift system of four tandem heli-copters carrying a load cooperatively.First,based on the hierarchical control,the load distribution problem is divided into two parts:the calculation of expected cable force and the calculation of the anti-disturbance cable force.Then,aimed at minimizing the maximum equivalent power of heli-copter,an optimization problem is set up to calculate the expected cable force.Specially,the agent power model is trained by BP neural network,the safe distance constraint between helicopters is set to 2.5 rotor diameters to reduce aerodynamic interference,and the helicopters with different perfor-mance can be considered by introducing the equivalent power factor into the objective function.Next,considering the difference and interaction between helicopters,the robust adaptive differen-tial game control is proposed to calculate the anti-disturbance cable force.Particularly,to solve the coupled Hamiltonian equations,an adaptive solving method for value function is proposed,and its stability is proved in the sense of Lyapunov.The simulation results indicate that the proposed load distribution method based on power consumption is applicable to the entire flight trajectory even there are differences between helicopters.The game control can consider interaction between heli-copters,can deal with different objective functions,and has strong robustness and small steady-state error.Based on the entire strategy,the cable force can be reasonably allocated so as to resist disturbance and improve the flight performance of the whole system.展开更多
The electrically driven large-load-ratio six-legged robot with engineering capability can be widely used in outdoor and planetary exploration.However,due to the particularity of its parallel structure,the effective ut...The electrically driven large-load-ratio six-legged robot with engineering capability can be widely used in outdoor and planetary exploration.However,due to the particularity of its parallel structure,the effective utilization rate of energy is not high,which has become an important obstacle to its practical application.To research the power consumption characteristics of robot mobile system is beneficial to speed up it toward practicability.Based on the configuration and walking modes of robot,the mathematical model of the power consumption of mobile system is set up.In view of the tripod gait is often selected for the six-legged robots,the simplified power consumption model of mobile system under the tripod gait is established by means of reducing the dimension of the robot’s statically indeterminate problem and constructing the equal force distribution.Then,the power consumption of robot mobile system is solved under different working conditions.The variable tendencies of the power consumption of robot mobile system are respectively obtained with changes in the rotational angles of hip joint and knee joint,body height,and span.The articulated rotational zones and the ranges of body height and span are determined under the lowest power consumption.According to the walking experiments of prototype,the variable tendencies of the average power consumption of robot mobile system are respectively acquired with changes in duty ratio,body height,and span.Then,the feasibility and correctness of theory analysis are verified in the power consumption of robot mobile system.The proposed analysis method in this paper can provide a reference on the lower power research of the large-load-ratio multi-legged robots.展开更多
We present an optically powered,intrinsically safe gas monitoring system to measure four essential environmental gases(CH_(4),CO_(2),CO and O_(2)),together with ambient temperature and pressure,for underground mines.T...We present an optically powered,intrinsically safe gas monitoring system to measure four essential environmental gases(CH_(4),CO_(2),CO and O_(2)),together with ambient temperature and pressure,for underground mines.The system is based on three key technologies developed at UNSW:(1)power-over-fbre(PoF)at 1550 nm using a single industry-standard,low-cost single-mode fbre(SMF)for both power delivery and information transmission,(2)liquid–crystal-based optical transducers for optical telemetry,and(3)ultra-low power consumption design of all electronics.Together,this approach allows each gas monitoring station to operate with less than 150 mW of optical power,meeting the intrinsic safety requirements specifed by the IEC60079-28 standard.A 2-month feld trial at BMA’s Broadmeadow underground mine proved the cabling compatibility to the mine’s existing optical network and the stability of the system performance.Compared with conventional electrically powered gas sensors,this technology bypasses the usual roadblocks of underground gas monitoring where electrical power is either unsafe or unavailable.Furthermore,using one fbre for both power delivery and communication enables longer distance coverage,reduces optical cabling and increases multiplexing possibilities and data throughput for better awareness of underground environment.展开更多
Bio-inspired computer modelling brings solutions fromthe living phenomena or biological systems to engineering domains.To overcome the obstruction problem of large-scale wind power consumption in Northwest China,this ...Bio-inspired computer modelling brings solutions fromthe living phenomena or biological systems to engineering domains.To overcome the obstruction problem of large-scale wind power consumption in Northwest China,this paper constructs a bio-inspired computer model.It is an optimal wind power consumption dispatching model of multi-time scale demand response that takes into account the involved high-energy load.First,the principle of wind power obstruction with the involvement of a high-energy load is examined in this work.In this step,highenergy load model with different regulation characteristics is established.Then,considering the multi-time scale characteristics of high-energy load and other demand-side resources response speed,a multi-time scale model of coordination optimization is built.An improved bio-inspired model incorporating particle swarm optimization is applied to minimize system operation and wind curtailment costs,as well as to find the most optimal energy configurationwithin the system.Lastly,we take an example of regional power grid in Gansu Province for simulation analysis.Results demonstrate that the suggested scheduling strategy can significantly enhance the wind power consumption level and minimize the system’s operational cost.展开更多
基金The authors gratefully express their appreciation to the National Natural Science Foundation of China(51834002)for sponsoring this work.
文摘Ladle furnaces are known for their high power consumption,making research on power-saving process crucial.In response to the defect of thin slag thickness in the industrial production of a 120-t ladle furnace at a steel plant,with its production of ship plate steel DH36 as the focus,experiments involving adding the foaming agent and shifting power delivery gears were conducted.Based on the principle of measuring alternating current by Rogowski coils,the power consumption during the ladle furnace refining process was calculated theoretically,and the actual industrial power consumption matched with it basically,confirming the accuracy of the theoretical calculations.Additionally,the impacts of argon flow rate,foaming agents,and shifting power delivery gears on power consumption were studied.The results showed that adding 0.59 and 0.50 kg/t foaming agents in two batches improved the refining process of the ladle furnace,allowing for effective submerged-arc operations and saving electric energy of 7.2382 kWh per ton of steel.Similarly,utilizing a power supply mode of 7-step short arc during the refining process significantly enhanced the desulfurization rate of molten steel and saved electric energy of 11.6387 kWh per ton of steel.
基金supported in part by the National Natural Science Foundation of China under Grants 62231009 and 62261160576in part by the Fundamental Research Funds for the Central Universities under Grant 2242023K5003in part by the Startup Research Fund of Southeast University under Grant RF1028623267。
文摘Reconfigurable intelligent surfaces(RISs)with the capability of nearly passive beamforming,have recently sparked considerable interests.This paper presents an energy-efficient discrete phase encoding method for RIS-assisted communication systems.Firstly,the beamforming gain,power consumption and energy efficiency models for the RIS-assisted system are illustrated.On this basis,the discrete phase encoding problem is formulated for the purpose of improving the energy efficiency,under the power constraint and the quality-of-service(QoS)requirement.According to the interrelation between the phase encoding and power consumption,a three-step encoding method is proposed with the capability of customizing the beamforming gain,power consumption,and energy efficiency.Simulation results indicate that the proposed method is capable of achieving a more favorable performance in terms of satisfying the QoS demand,reducing the power consumption,and improving the energy efficiency.Furthermore,two field trials at 35 GHz evidence the superiority performance and feasibility characteristics of the proposed method in real environment.This work may provide a reference for future applications of RIS-assisted system with an energy-efficient manner.
文摘The rapid evolution and expanding scale of AI(artificial intelligence)technologies exert unprecedented energy demands on global electrical grids.Powering computationally intensive tasks such as large-scale AI model training and widespread real-time inference necessitates substantial electricity consumption,presenting a significant challenge to conventional power infrastructure.This paper examines the critical need for a fundamental shift towards smart energy grids in response to AI’s growing energy footprint.It delves into the symbiotic relationship wherein AI acts as a significant energy consumer while offering the intelligence required for dynamic load management,efficient integration of renewable energy sources,and optimized grid operations.We posit that advanced smart grids are indispensable for facilitating AI’s sustainable growth,underscoring this synergy as a pivotal advancement toward a resilient energy future.
基金funded by the National Key Research and Development Program of China(2024YFE0106800)Natural Science Foundation of Shandong Province(ZR2021ME199).
文摘The intermittency and volatility of wind and photovoltaic power generation exacerbate issues such as wind and solar curtailment,hindering the efficient utilization of renewable energy and the low-carbon development of energy systems.To enhance the consumption capacity of green power,the green power system consumption optimization scheduling model(GPS-COSM)is proposed,which comprehensively integrates green power system,electric boiler,combined heat and power unit,thermal energy storage,and electrical energy storage.The optimization objectives are to minimize operating cost,minimize carbon emission,and maximize the consumption of wind and solar curtailment.The multi-objective particle swarm optimization algorithm is employed to solve the model,and a fuzzy membership function is introduced to evaluate the satisfaction level of the Pareto optimal solution set,thereby selecting the optimal compromise solution to achieve a dynamic balance among economic efficiency,environmental friendliness,and energy utilization efficiency.Three typical operating modes are designed for comparative analysis.The results demonstrate that the mode involving the coordinated operation of electric boiler,thermal energy storage,and electrical energy storage performs the best in terms of economic efficiency,environmental friendliness,and renewable energy utilization efficiency,achieving the wind and solar curtailment consumption rate of 99.58%.The application of electric boiler significantly enhances the direct accommodation capacity of the green power system.Thermal energy storage optimizes intertemporal regulation,while electrical energy storage strengthens the system’s dynamic regulation capability.The coordinated optimization of multiple devices significantly reduces reliance on fossil fuels.
基金The National Natural Science Foundation of China(No. 61106024)the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20090092120012)the Science and Technology Program of South east University (No. KJ2010402)
文摘A 37. 5 MHz differential complementary metal oxide semiconductor （CMOS） crystal oscillator with low power and low phase noise for the radio frequency tuner of digital radio broadcasting digital radio mondiale （DRAM） and digital audio broadcasting （DAB） systems is realized and characterized. The conventional cross-coupled n-type metal oxide semiconductor （NMOS） transistors are replaced by p-type metal oxide semiconductor （PMOS） transistors to decrease the phase noise in the core part of the crystal oscillator. A symmetry structure of the current mirror is adopted to increase the stability of direct current. The amplitude detecting circuit made up of a single- stage CMOS operational transconductance amplifier （OTA） and a simple amplitude detector is used to improve the current accuracy of the output signals. The chip is fabricated in a 0. 18- pxn CMOS process, and the total chip size is 0. 35 mm x 0. 3 mm. Under a supply voltage of 1.8 V, the measured power consumption is 3.6 mW including the output buffer for 50 testing loads. The proposed crystal oscillator exhibits a low phase noise of - 134. 7 dBc/Hz at 1-kHz offset from the center frequency of 37. 5 MHz.
基金The National Basic Research Program of China (973Program) (No.2003CB314702).
文摘The power consumption and electric field distribution in a field emission display （FED） panel is optimized with a novel pixel structure. A circuit model is proposed to estimate the total power consumption in an FED panel which is composed of anode energy consumption, energy loss due to the leakage current and the energy dissipated in the parasitic capacitances. Moreover, the parasitic capacitances play a vital part in the power consumption and driving performance. In order to lower the parasitic capacitances, multiple dielectric layers are used as the gate electrode. Due to different etching speeds, a novel pixel structure is formed. As a result, the power consumption of an FED panel is reduced by 28% in a full white picture, and the electron beam performance is also better than that of the conventional structure.
基金The National Basic Research Program of China,No.2010CB950901National Natural Science Foundation of China,No.40971059
文摘Electric power consumption(EPC)is one of the basic indices for evaluating electric power use.Obtaining timely and accurate data on the spatiotemporal dynamics of EPC is crucial for understanding and practical deployment of electric power resources.In this study,an EPC model was developed using stable nighttime lights time-series data from the Defense Meteorological Satellite Program Operational Linescan System(DMSP/OLS).The model was used to reconstruct the spatial patterns of EPC in Chinese Mainland at the county level from 1995 to 2008.In addition,the spatiotemporal dynamics of EPC were analyzed,and the fol-lowing conclusions were drawn.(1)The EPC model reliably represented the spatiotemporal dynamics of EPC in Chinese Mainland with approximately 70%accuracy.(2)The EPC in most regions of Chinese Mainland was at low to moderate levels,with marked temporal and spatial variations;of high-level EPC,58.26%was concentrated in eastern China.Six urban agglomerations(Beijing-Tianjin-Tangshan region,Shanghai-Nanjing-Hangzhou region,Pearl River Delta,Shandong Peninsula,middle-south of Liaoning Province,and Sichuan Basin)accounted for 10.69%of the total area of Chinese Mainland but consumed 39.23%of the electricity.(3)The EPC of most regions in Chinese Mainland increased from 1995 to 2008,and 64%of the mainland area showed a significant increase in EPC.Moderate increases in EPC were found in 61.62%of eastern China and 80.65%of central China from 1995 to 2008,whereas 75.69%of western China showed no significant increase in EPC.Meanwhile,77.27%,89.35%,and 66.72%of the Shanghai-Nanjing-Hangzhou region,Pearl River Delta,and Shandong Peninsula,respectively,showed high-speed increases in EPC.Moderate increases in EPC occurred in 71.12%and 72.13%of the Beijing-Tianjin-Tangshan region and middle-south of Liaoning Province,respectively,while no significant increase occurred in 56.34%of the Sichuan Basin.
基金Supported by the Fundamental Research Funds for the Central Universities(2012QNA4018)the National Natural Science foundation of China(21206144)the Program for Zhejiang Leading Team of S&T Innovation(2011R50005)
文摘A coaxial mixer meeting the actual demand of a system with high and variable viscosity is investigated. It has an outer wall-scraping frame and a double inner impeller consisting of a four-pitched-blade turbine and Rushton turbine. The power consumption and flow field characteristics of the coaxial mixer in laminar and transitional flow are simulated numerically, and then the distribution of velocity field, shear rate and mass flow rate are analyzed. The simulation results indicate that the outer frame has little effect on the power consumption of the double inner impeller whether in laminar or transitional flow, whereas the inner combined impeller has a great effect on the power consumption of the outer frame. Compared with the single rotation mode, the power consumption of the outer frame will decrease in co-rotation mode and increase in counter-rotation mode. The velocity, shear rate and mass flow rate are relatively high near the inner impeller in all operating modes, and only under double-shaft agitation will the mixing performance near the free surface be improved.In addition, these distributions in the co-rotation and counter-rotation modes show little difference, but the co-rotation mode is recommended for the advantage of low power consumption.
文摘The role of baffles in mechanically stirred tanks is to promote the stability of power drawn by the impeller and to avoid the fluid swirling, thus enhancing mixing. The present paper numerically investigates the baffles effects in a vessel stirred by a Rushton turbine. The geometric factor of interest is the baffle inclination which is varying between 25°, 32.5°, 45°, 70° and 90° at different impeller rotational speeds. The impeller rotational direction has also been varied. The vortex size and power consumption were evaluated for each geometrical configuration. It was found that the best configuration is the baffle inclination by = 70° at a negative angular velocity.
基金Project supported by the National High Technology Research and Development Program of China(Grant No.2015AA016902)the National Nature Science Foundation of China(Grant Nos.61435013,61405188,and 61627820)
文摘The power consumption of a variable optical attenuator（VOA） array based on a silica planar lightwave circuit was investigated. The thermal field profile of the device was optimized using the finite-element analysis. The simulation results showed that the power consumption reduces as the depth of the heat-insulating grooves is deeper, the up-cladding is thinner,the down-cladding is thicker, and the width of the cladding ridge is narrower. The materials component and thickness of the electrodes were also optimized to guarantee the driving voltage under 5 V. The power consumption was successfully reduced to as low as 155 mW at an attenuation of 30 dB in the experiment.
基金the National Natural Science Foundation of China[51475403],and the financial support to the author is gratefully acknowledged.References。
文摘Discrete element method(DEM)simulations of particle mixing process in an intensive mixer were conducted to study the influence of structural and process parameters on the mixing performance and power consumption.The DEM model was verified by comparing the impeller torque obtained from simulation with that from experiment.Impeller and vessel torque,coordination number(CN)and mixing index(Relative standard deviation)were adopted to qualify the particle dynamics and mixing performance with different parameters.A method based on cubic polynomial fitting was proposed to determine the critical mixing time and critical specific input work during the mixing process.It is found that the mixing performance and energy efficiency increases with the decrease of impeller offset.The mixing performance is improved slightly with the increase of blade number and the impeller with 3 blades has the highest energy efficiency due to its low input torque.Results indicate that the energy efficiency and the mixing performance increase with the decrease of filling level when the height of granular bed is higher than that of blade.
基金The finance supporting from National High Technical Research and Development Program of China(863program)2014AA01A705
文摘A new power estimation method is proposed for base station(BS) in this paper.Based on this method,a software platform for power estimation is developed.The proposed method models power consumption on different abstraction levels by splitting a typical base station into several basic components at different levels in the view of embedded system design.In particular,our focus is on baseband IC(Integrate Circuit) due to it's the dominant power consumer in small cells.Baseband power model is based on arithmetic computing costs of selected algorithms.All computing and storage costs are calibrated using algorithm complexity,hardware architecture,activity ratio,silicon technology,and overheads on all hierarchies.Micro architecture and IC technology are considered.The model enables power comparison of different types of base stations configured with different baseband algorithms,micro architectures,and ICs.The model also supports cellular operators in power estimation of different deployment strategies and transmission schemes.The model is verified by comparing power consumption with a real LTE base station.By exposing more configuration freedoms,the platform can be used for power estimation of current and future base stations.
基金Project supported by the Hi-Tech Research and Development Program (863) of China (No. 2006AA01Z226)the Scientific Research Foundation of Huazhong University of Science and Technol-ogy (No. 2006Z001B), China
文摘Using composite field arithmetic in Galois field can result in the compact Rijndael S-Box. However, the power con- sumption of this solution is too large to be used in resource-limited embedded systems. A full-custom hardware implementation of composite field S-Box is proposed for these targeted domains in this paper. The minimization of power consumption is implemented by optimizing the architecture of the composite field S-Box and using the pass transmission gate (PTG) to realize the logic functions of S-Box. Power simulations were performed using the netlist extracted from the layout. HSPICE simulation results indicated that the proposed S-Box achieves low power consumption of about 130 μW at 10 MHz using 0.25 μm/2.5 V technology, while the consumptions of the positive polarity reed-muller (PPRM) based S-Box and composite field S-Box based on the conventional CMOS logic style are about 240 μW and 420 μW, respectively. The simulations also showed that the presented S-Box obtains better low-voltage operating property, which is clearly relevant for applications like sensor nodes, smart cards and radio frequency identification (RFID) tags.
基金Supported by the National Basic Research Program of China under Grant No 2013CB632801the National Key Research and Development Program under Grant No 2016YFB0402303+2 种基金the National Natural Science Foundation of China under Grant Nos61435014,61627822,61574136 and 61306058the Key Projects of Chinese Academy of Sciences under Grant No ZDRW-XH-2016-4the Beijing Natural Science Foundation under Grant No 4162060
文摘We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. For a 2-mm-long and 10-μm-wide laser coated with high-reflectivity on the rear facet, more than 170mW of output power is obtained at 20℃ with a threshold power consumption of 2.4 W, corresponding to 30mW with a threshold power consumption of 3.9 W at 90℃. Robust single-mode emission with a side-mode suppression ratio above 25 dB is continuously tunable by the heat sink temperature or injection current.
文摘A test pattern generator （TPG） which can highly reduce the peak power consumption during built-in self-test （BIST） application is proposed. The proposed TPG, called LPpe-TPG, consists of a linear feedback shift register （LFSR） and some control circuits. A procedure is presented firstly to make compare vectors between pseudorandom test patterns by adding some circuits to the original LFSR and secondly to insert some vectors between two successive pseudorandom test patterns according to the ordinal selection of every two bits of the compare vector. Then the changes between any successive test patterns of the test set generated by the LPpe-TPG are not more than twice. This leads to a decrease of the weighted switching activity （WSA） of the circuit under test （CUT） and therefore a reduction of the power consumption. Experimental results based on some ISCAS＇ 85 benchmark circuits show that the peak power consumption has been reduced by 25.25% to 64.46%. Also, the effectiveness of our approach to reduce the total and average power consumption is kept, without losing stuck-at fault coverage.
文摘It is of great significance to reasonably distribute the slung load to each helicopter while considering difference in power consumption,relative position and interaction comprehensively.Therefore,the load distribution strategy based on power consumption and robust adaptive game control is proposed in this paper.The study is on a"2-lead"multi-lift system of four tandem heli-copters carrying a load cooperatively.First,based on the hierarchical control,the load distribution problem is divided into two parts:the calculation of expected cable force and the calculation of the anti-disturbance cable force.Then,aimed at minimizing the maximum equivalent power of heli-copter,an optimization problem is set up to calculate the expected cable force.Specially,the agent power model is trained by BP neural network,the safe distance constraint between helicopters is set to 2.5 rotor diameters to reduce aerodynamic interference,and the helicopters with different perfor-mance can be considered by introducing the equivalent power factor into the objective function.Next,considering the difference and interaction between helicopters,the robust adaptive differen-tial game control is proposed to calculate the anti-disturbance cable force.Particularly,to solve the coupled Hamiltonian equations,an adaptive solving method for value function is proposed,and its stability is proved in the sense of Lyapunov.The simulation results indicate that the proposed load distribution method based on power consumption is applicable to the entire flight trajectory even there are differences between helicopters.The game control can consider interaction between heli-copters,can deal with different objective functions,and has strong robustness and small steady-state error.Based on the entire strategy,the cable force can be reasonably allocated so as to resist disturbance and improve the flight performance of the whole system.
基金National Natural Science Foundation of China(Grant No.51505335)Industry University Cooperation Collaborative Education Project of the Department of Higher Education of the Ministry of Education of China(Grant No.202102517001)Doctor Startup Projects of TUTE of China(Grant No.KYQD1806)。
文摘The electrically driven large-load-ratio six-legged robot with engineering capability can be widely used in outdoor and planetary exploration.However,due to the particularity of its parallel structure,the effective utilization rate of energy is not high,which has become an important obstacle to its practical application.To research the power consumption characteristics of robot mobile system is beneficial to speed up it toward practicability.Based on the configuration and walking modes of robot,the mathematical model of the power consumption of mobile system is set up.In view of the tripod gait is often selected for the six-legged robots,the simplified power consumption model of mobile system under the tripod gait is established by means of reducing the dimension of the robot’s statically indeterminate problem and constructing the equal force distribution.Then,the power consumption of robot mobile system is solved under different working conditions.The variable tendencies of the power consumption of robot mobile system are respectively obtained with changes in the rotational angles of hip joint and knee joint,body height,and span.The articulated rotational zones and the ranges of body height and span are determined under the lowest power consumption.According to the walking experiments of prototype,the variable tendencies of the average power consumption of robot mobile system are respectively acquired with changes in duty ratio,body height,and span.Then,the feasibility and correctness of theory analysis are verified in the power consumption of robot mobile system.The proposed analysis method in this paper can provide a reference on the lower power research of the large-load-ratio multi-legged robots.
基金support of the Australian Coal Industry’s Research Program(ACARP Grant C28010).
文摘We present an optically powered,intrinsically safe gas monitoring system to measure four essential environmental gases(CH_(4),CO_(2),CO and O_(2)),together with ambient temperature and pressure,for underground mines.The system is based on three key technologies developed at UNSW:(1)power-over-fbre(PoF)at 1550 nm using a single industry-standard,low-cost single-mode fbre(SMF)for both power delivery and information transmission,(2)liquid–crystal-based optical transducers for optical telemetry,and(3)ultra-low power consumption design of all electronics.Together,this approach allows each gas monitoring station to operate with less than 150 mW of optical power,meeting the intrinsic safety requirements specifed by the IEC60079-28 standard.A 2-month feld trial at BMA’s Broadmeadow underground mine proved the cabling compatibility to the mine’s existing optical network and the stability of the system performance.Compared with conventional electrically powered gas sensors,this technology bypasses the usual roadblocks of underground gas monitoring where electrical power is either unsafe or unavailable.Furthermore,using one fbre for both power delivery and communication enables longer distance coverage,reduces optical cabling and increases multiplexing possibilities and data throughput for better awareness of underground environment.
基金supported by the Program for Innovative Research Team(in Science and Technology)in University of Henan Province(No.22IRTSTHN016)the Hubei Natural Science Foundation(No.2021CFB156)the Japan Society for the Promotion of Science(JSPS)Grants-in-Aid for Scientific Research(KAKENHI)(No.JP21K17737).
文摘Bio-inspired computer modelling brings solutions fromthe living phenomena or biological systems to engineering domains.To overcome the obstruction problem of large-scale wind power consumption in Northwest China,this paper constructs a bio-inspired computer model.It is an optimal wind power consumption dispatching model of multi-time scale demand response that takes into account the involved high-energy load.First,the principle of wind power obstruction with the involvement of a high-energy load is examined in this work.In this step,highenergy load model with different regulation characteristics is established.Then,considering the multi-time scale characteristics of high-energy load and other demand-side resources response speed,a multi-time scale model of coordination optimization is built.An improved bio-inspired model incorporating particle swarm optimization is applied to minimize system operation and wind curtailment costs,as well as to find the most optimal energy configurationwithin the system.Lastly,we take an example of regional power grid in Gansu Province for simulation analysis.Results demonstrate that the suggested scheduling strategy can significantly enhance the wind power consumption level and minimize the system’s operational cost.
