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A Workable Solution for Reducing the Large Number of Vehicle and Pedestrian Accidents Occurring on a Yellow Light
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作者 Pranav Gupta Silki Arora 《Journal of Transportation Technologies》 2024年第1期82-87,共6页
Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada... Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada, during 2019, the National Collision Database shows that 28% of traffic fatalities and 42% of serious injuries occurred at intersections. Likewise, the U.S. National Highway Traffic Administration (NHTSA) found that about 40% of the estimated 5,811,000 accidents in the U.S. during the year studied were intersection-related crashes. In fact, a major survey by the car insurance industry found that nearly 85% of drivers could not identify the correct action to take when approaching a yellow traffic light at an intersection. One major reason for these accidents is the “yellow light dilemma,” the ambiguous situation where a driver should stop or proceed forward when unexpectedly faced with a yellow light. This situation is even further exacerbated by the tendency of aggressive drivers to inappropriately speed up on the yellow just to get through the traffic light. A survey of Canadian drivers conducted by the Traffic Injury Research Foundation found that 9% of drivers admitted to speeding up to get through a traffic light. Another reason for these accidents is the increased danger of making a left-hand turn on yellow. According to the National Highway Traffic Safety Association (NHTSA), left turns occur in approximately 22.2% of collisions—as opposed to just 1.2% for right turns. Moreover, a study by CNN found left turns are three times as likely to kill pedestrians than right turns. The reason left turns are so much more likely to cause an accident is because they take a driver against traffic and in the path of oncoming cars. Additionally, most of these left turns occur at the driver’s discretion—as opposed to the distressingly brief left-hand arrow at busy intersections. Drive Safe Now proposes a workable solution for reducing the number of accidents occurring during a yellow light at intersections. We believe this fairly simple solution will save lives, prevent injuries, reduce damage to public and private property, and decrease insurance costs. 展开更多
关键词 Traffic Accidents Yellow Light Traffic Light Signals INTERSECTION Crashes Collision Traffic Fatalities Traffic Injuries Vehicles SAFETY Speed Limit Driving Pedestrians Bicyclists MOTORCYCLISTS Caution Line Yellow Light Dilemma Left Hand Turn on Yellow Distance Smart Road Technology Signs Signage Autonomous Vehicles AVs Road Safety IoT Internet of Things Infrastructure Accident Reduction Driving Habits Stop Line Red Light Jumping Pedestrian Safety Caution Light Stopping at Intersection Safety at Intersections
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NASA’s EM Drive Thrust from the Forces of the Quantum Vacuum of Spacetime
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作者 Mohamed S. El Naschie 《Advances in Aerospace Science and Technology》 2018年第1期1-9,共9页
Building on the various manifestations of the forces latent in the quantum vacuum of spacetime such as Hawking’s radiation and Unruh temperature, we resolve a major paradox connected to an immensely important proposa... Building on the various manifestations of the forces latent in the quantum vacuum of spacetime such as Hawking’s radiation and Unruh temperature, we resolve a major paradox connected to an immensely important proposal by NASA scientists for constructing a practically fuelless spacecraft. In a nutshell, preliminary laboratory work shows that NASA’s electromagnetic drive project is viable and several experiments and measurements show it is real. Yet the proposal violates a fundamental principle of classical mechanics, namely Newton’s third law. The resolution of this paradox is quite straight forward in principle. It is simply the case that although the proposal seems to be based on classical mechanics and classical thinking it is only superficially so. Deep at the roots, the EM drive proposal of NASA is not classical physics but rather based on the vacuum forces of quantum cosmology and the theory of dark energy density of the universe. In fact the proposal is deeply linked to Hawking’s radiation and Unruh temperature, which is explained in some detail in the main body of the present short paper within the frame work of E-infinity Cantorian spacetime theory and D. Gross’ Heterotic superstring theory. In short the quintessence of our explanation is to regard the EM drive as a quasi electromagnetic cavity with an effective event horizon akin to that of a Hawking black hole emitting radiation causing ultimately the needed thrust to push the spacecraft forwards. In addition and by invoking fractal spacetime self similarity we show that a spacecraft will be subject to another cosmic thrust on the large scale of the entire cosmos. 展开更多
关键词 EM drive Interstellar Flight Vacuum ENERGY DARK ENERGY Cantorian SPACETIME Hartle-Hawking Wave Function of the Cosmos Cantorian Plasma Quantum Cosmology Casimir-Dark ENERGY Nano Reactor Heterotic SUPERSTRINGS Equations of Ordinary and DARK ENERGY Nonlinear Dynamics and Fractals Hawking Radiation Axion Unruh Temperature
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Thoughts on Pairing Assistance to Tibet for Promoting Agricultural High-quality Development in Southern Tibet from the Perspective of Agricultural Power
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作者 Zhiguo SUN Li GAO +3 位作者 Yuanpeng SUN Guangchao CAO Xinying ZHOU Xiaoqiang LI 《Asian Agricultural Research》 2024年第3期18-24,共7页
In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style mod... In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style modernization.Southern Tibet,located in the southeastern part of the Tibet Autonomous Region,includes Shannan City and Nyingchi City,is a region assisted by four provincial partners including Hubei Province.This paper introduces the agricultural environment in southern Tibet,studies its agricultural characteristics,and analyzes the main issues of its pairing assistance.Taking forging the strong consciousness of the Chinese national community as the main line,the paper explores strategies for promoting agricultural high-quality development in southern Tibet through pairing assistance to Tibet from the perspective of agricultural power,and proposes some strategies,such as inheriting agricultural cultural heritage,promoting the upgrading of modern seed industry,enhancing the characteristic advantages of highland barley(naked barley)and animal husbandry industries,and developing edible fungi and cold water fish industries. 展开更多
关键词 PAIRING ASSISTANCE to TIBET Southern TIBET Shannan CITY Nyingchi CITY AGRICULTURAL high-quality development AGRICULTURAL power
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Reducing Peak-to-Average Power Ratio of a Turbo Coded OFDM
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作者 Spyridon K. Chronopoulos Vasilis Christofilakis +1 位作者 Giorgos Tatsis Panos Kostarakis 《Wireless Engineering and Technology》 2012年第4期195-202,共8页
Peak to Average Power Ratio (PAPR) is defined as the instantaneous power (maximum value) to the average power ratio. PAPR is considered to be a major problem in OFDM systems. This problem can cause radical unexpected ... Peak to Average Power Ratio (PAPR) is defined as the instantaneous power (maximum value) to the average power ratio. PAPR is considered to be a major problem in OFDM systems. This problem can cause radical unexpected behavior of the signal fluctuation. This fluctuation is constituted by a large number of power states. The enormous number of these states leads to an additional complexity of ADCs and DACs. This research addresses the previous problem in OFDM systems utilizing Turbo Codes. μLaCP technique is employed for the purpose of decreasing PAPR. Moreover, our OFDM system was simulated in the presence of an AWGN channel with four types of codes (without the presence of ADCs and DACs). These were constituted of PCCC (typical and new), SCCC, and Convolutional Codes. Our Turbo Coded OFDM exhibited unchanged BER performance before and after the use of μLaCP technique. This was accomplished by modifying our previous PAPR reduction technique without sacrificing greatly its attributes. 展开更多
关键词 Orthogonal Frequency Division Multiplexing PEAK to Average power RATIO μ-Law μLaCP μLaIF Parallel CONCATENATED Convolutional Codes A POSTERIORI Probability Cyclic PREFIX Zero PADDING PEAK RATIO Bit Error Rate
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Optimal Power Allocation Strategy for TBLAST Based 4G Systems
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作者 Wu YIN Pei XIAO 《Engineering(科研)》 2009年第2期91-98,共8页
There is a big demand for increasing number of subscribers in the fourth generation mobile communication systems. However, the system performance is limited by multi-path propagations and lack of efficient power alloc... There is a big demand for increasing number of subscribers in the fourth generation mobile communication systems. However, the system performance is limited by multi-path propagations and lack of efficient power allocation algorithms in conventional wireless communication systems. Optimal resource allocation and interference cancellation issues are critical for the improvement of system performance such as throughput and transmission reliability. In this paper, a turbo coded bell lab space time system (TBLAST) with optimal power allocation techniques based on eigen mode, Newton and convex optimization method and carrier-interference-and-noise ratio (CINR) are proposed to improve link reliability and to increase throughput with reasonable computational complexity. The proposed scheme is evaluated by Monte-Carlo simulations and is shown to outperform the conventional power allocation scheme. 展开更多
关键词 Carrier Interference and Noise Ratio (CINR) Convolutional TURBO CODED BELL Space Time (TBLAST) EIGEN Mode (EM) Optimal power Allocation (OPL) Automatic Differentiation (AD) SYMBOLIC DERIVATIVE (S
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Oxidation Kinetics of Aluminum Powders in a Gas Fluidized Bed Reactor in the Potential Application of Surge Arresting Materials
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作者 Hong Shih 《Materials Sciences and Applications》 2019年第3期253-292,共40页
In this technical paper, the oxidation mechanism and kinetics of aluminum powders are discussed in great details. The potential applications of spherical aluminum powders after oxidation to be part of the surging arre... In this technical paper, the oxidation mechanism and kinetics of aluminum powders are discussed in great details. The potential applications of spherical aluminum powders after oxidation to be part of the surging arresting materials are discussed. Theoretical calculations of oxidation of spherical aluminum powders in a typical gas fluidization bed are demonstrated. Computer software written by the author is used to carry out the basic calculations of important parameters of a gas fluidization bed at different temperatures. A mathematical model of the dynamic system in a gas fluidization bed is developed and the analytical solution is obtained. The mathematical model can be used to estimate aluminum oxide thickness at a defined temperature. The mathematical model created in this study is evaluated and confirmed consistently with the experimental results on a gas fluidization bed. Detail technical discussion of the oxidation mechanism of aluminum is carried out. The mathematical deviations of the mathematical modeling have demonstrated in great details. This mathematical model developed in this study and validated with experimental results can bring a great value for the quantitative analysis of a gas fluidization bed in general from a theoretical point of view. It can be applied for the oxidation not only for aluminum spherical powders, but also for other spherical metal powders. The mathematical model developed can further enhance the applications of gas fluidization technology. In addition to the development of mathematical modeling of a gas fluidization bed reactor, the formation of oxide film through diffusion on both planar and spherical aluminum surfaces is analyzed through a thorough mathematical deviation using diffusion theory and Laplace transformation. The dominant defects and their impact to oxidation of aluminum are also discussed in detail. The well-controlled oxidation film on spherical metal powders such as aluminum and other metal spherical powders can potentially become an important part of switch devices of surge arresting materials, in general. 展开更多
关键词 Aluminum Spherical power GAS FLUIDIZATION Bed Oxidation Mechanism Oxide Growth Rate Gibbs Free Energy Ellingham Diagram Mathematical Modeling Dynamic System Plasma DIFFUSION DIFFUSION Coefficient Crystallographic Defect Vacancy Pressure Temperature Flow Laplace Transform Equation Boundary Condition Ficks Second Law Software Experimental Theoretical SURGE ARRESTING MATERIALS Analytical Solution
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Comparative Study of Radiological Changes in Hands and Feet in Patients Suffering from Early Rheumatoid Arthritis by Power Doppler Ultrasound and Direct Digital Radiography
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作者 Gargy Mondal Biswadip Ghosh +1 位作者 Manoranjan Ghosh Pampa Halder 《Open Journal of Rheumatology and Autoimmune Diseases》 2014年第1期39-42,共4页
Rheumatoid arthritis is a chronic multisystem disease of unknown cause. The characteristic feature of RA is persistent inflammatory synovitis. The natural history of disease is such that the early months of the diseas... Rheumatoid arthritis is a chronic multisystem disease of unknown cause. The characteristic feature of RA is persistent inflammatory synovitis. The natural history of disease is such that the early months of the disease are critical period during which reversible joint damage occurs. So early diagnosis of RA and appropriate drug application is the only way to save a patient from this crippling disease. In India, the cost of investigations is a significant factor for most of the patients. Ultrasonography or Power Doppler Ultra Sound (PDUS) has the advantage of being economic in spite of its sensitivity in assessing both inflammatory and destructive changes. The aim of the present study was to evaluate the diagnostic efficiency of PDUS in early rheumatoid arthritis. The study was performed with the patients attending Rheumatology Clinic. A total number of 106 patients of clinically suspected rheumatoid arthritis were studied as per selection criteria. Radiological examinations of hands were done by digital radiography and PDUS in a group of 53 patients, assessment of foot changes by PDUS and Digital Radiography were done in another similar group of 53 patients. Final diagnosis by ACR EULAR-2010 criteria is done for all the patients. The comparative study reveals that synovial vascularity as demonstrated by PDUS is much more effective in diagnosing early rheumatoid arthritis, both in hand and in feet than digital radiograph. PDUS of feet may yield earlier and better findings than hands, which is conventionally used in patients suffering from early rheumatoid arthritis. 展开更多
关键词 R.A.Rheumatoid Arthritis PDUS—power Doppler Ultrasound D.R.Digital Radiography ACR-EULARAmerican College of RHEUMATOLOGY (ACR) and the European LEAGUE against RHEUMATISM (EULAR) RFRheumatoid Factor CRPc-Reactive Protein MRIMagnetic Resonance Imaging
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Performance Analysis of Induced Draft Fan Driven by Steam Turbine for 1000 MW Power Units 被引量:3
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作者 Jianling Deng Feifei Liang +3 位作者 Yang Ding Zhiping Yang Gang Xu Jizhen Liu 《Energy and Power Engineering》 2013年第4期1387-1392,共6页
Boiler fan is the main power consumption device in thermal power units and the induced draft fan accounted for the largest proportion. Reducing the energy consumption rate of induced draft fan is the main path to redu... Boiler fan is the main power consumption device in thermal power units and the induced draft fan accounted for the largest proportion. Reducing the energy consumption rate of induced draft fan is the main path to reduce the power consumption rate of thermal power units. The induce fan driven by small turbine is greatly effective for reducing the power consumption rate and the supply coal consumption rate in large thermal power plant. Take 1000 MW power units for example, the selection of steam source for steam turbine were discussed and economic performance of the unit under different steam source was compared in this paper. The result shows that compared with the motor driven method, there is about 1.6 g/kWh decrease in supply coal consumption rate driven by the fourth stage extraction steam;whereas there is about 2.5 g/kWh decrease in supply coal consumption rate driven by the fifth stage extraction steam. 展开更多
关键词 Induced Draft FAN Source Steam AUXILIARY power Ratio Supply Coal CONSUMPTION Rate INVESTMENT Recovery PERIOD
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德国历史学派与19世纪经济学方法论之争的启示 被引量:17
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作者 何蓉 《社会》 北大核心 2005年第3期167-186,共20页
In the mid-19th century, out of their dissatisfaction with the neglect of the economic theories about other countries’ experiences in the British classic economics, the economists in the German Historical School wo... In the mid-19th century, out of their dissatisfaction with the neglect of the economic theories about other countries’ experiences in the British classic economics, the economists in the German Historical School worked hard to construct an economic theory that was congruent to the developmental stage in their own country’s culture and history. Their deeply-cherished concern about the reality in a transitional era when Germany was approaching modernization drove them to propose that the living condition of the working class be improved by the power of the state. In the late 80’s of the same century, the Methodenstreit of German Historical School versus the Austrian School broke out, after which the mainstream economics was well on its way in terms of theoretical refinement and scrutiny, whereas the influence from the Historical School gradually subsided. Even so, the lessons from the Historical School are still enlightening to research in contemporary social sciences. This paper describes the unique basics in the theory building of the Historical School; explains the background and meaning of its academic origin, research methodology, and the Methodenstreit; and from there, discusses implications for contemporary social sciences. 展开更多
关键词 19 School ACADEMIC culture science about from origin that other and power after which STILL there with hard when LATE well This its of to way are for In be on so
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Design and Analysis of a Power Efficient Linearly Tunable Cross-Coupled Transconductor Having Separate Bias Control
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作者 Vijaya Bhadauria Krishna Kant Swapna Banerjee 《Circuits and Systems》 2012年第1期99-106,共8页
A common current source, generally used to bias cross-coupled differential amplifiers in a transconductor, controls third harmonic distortion (HD3) poorly. Separate current sources are shown to provide better control ... A common current source, generally used to bias cross-coupled differential amplifiers in a transconductor, controls third harmonic distortion (HD3) poorly. Separate current sources are shown to provide better control on HD3) . In this paper, a detailed design and analysis is presented for a transconductor made using this biasing technique. The transconductor, in addition, is made to offer high Gm, low power dissipation and is designed for linearly tunable Gm with current mode load as one of the applications. The circuit exhibits HD3) of less than –43.7 dB, high current efficiency of 1.18 V-1 and Gm of 390 μS at 1 VGp-p @ 50 MHz. UMC 0.18 μm CMOS process technology is used for simulation at supply voltage of 1.8 V. 展开更多
关键词 ANALOG electronics low power ANALOG CMOS Circuit Operational TRANSCONDUCTANCE Amplifier (OTA) Multiple-output OTA (MOTA) MOS TRANSCONDUCTORS LINEARLY TUNABLE Gm Current efficiency Linearization Techniques Harmonic Distortion Analysis
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A Decision Support System for Selection of Solar Power Plant Locations by Applying Fuzzy AHP and TOPSIS: An Empirical Study 被引量:2
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作者 Athakorn Kengpol Piya Rontlaong Markku Tuominen 《Journal of Software Engineering and Applications》 2013年第9期470-481,共12页
The objective of this research is to propose a decision support system for avoiding flood on solar power plant site selection. Methodologically, the geographic information system (GIS) is used to determine the optimum... The objective of this research is to propose a decision support system for avoiding flood on solar power plant site selection. Methodologically, the geographic information system (GIS) is used to determine the optimum site for a solar power plant. It is intended to integrate the qualitative and quantitative variables based upon the adoption of the Fuzzy Analytic Hierarchy Process (Fuzzy AHP) and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) model. These methods are employed to unite the environmental aspects and social needs for electrical power systematically. Regarding a case study of the choice of a solar power plant site in Thailand, it demonstrates that the quantitative and qualitative criteria should be realized prior to analysis in the Fuzzy AHP-TOPSIS model. The fuzzy AHP is employed to determine the weights of qualitative and quantitative criteria that can affect the selection process. The adoption of the fuzzy AHP is aimed to model the linguistic unclear, ambiguous, and incomplete knowledge. Additionally, TOPSIS, which is a ranking multi-criteria decision making method, is employed to rank the alternative sites based upon overall efficiency. The contribution of this paper lies in the evolution of a new approach that is flexible and practical to the decision maker, in providing the guidelines for the solar power plant site choices under stakeholder needs: at the same time, the desirable functions are achieved, in avoiding flood, reducing cost, time and causing less environmental impact. The new approach is assessed in the empirical study during major flooding in Thailand during the fourth quarter of 2011 to 2012. The result analysis and sensitivity analysis are also presented. 展开更多
关键词 Solar power Plant Site SELECTION Decision Support System Fuzzy ANALYTIC Hierarchy Process (FAHP) Technique for Order PREFERENCE by Similarity to IDEAL Solution (TOPSIS)
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Theory of Electromagnetism and Gravity —Modeling Earth as a Rotating Solenoid Coil
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作者 Greg Poole 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第4期663-692,共30页
Presented in this manuscript are conventional electrical engineering tools to model the earth as a rotating electrical machine. Calculations using known parameters of the earth and measured field data has resulted in ... Presented in this manuscript are conventional electrical engineering tools to model the earth as a rotating electrical machine. Calculations using known parameters of the earth and measured field data has resulted in new understanding of the earth’s electrical system and gyroscopic rotation. The material makeup of the inner earth is better understood based on derived permeability and permittivity constants. The planet has been modeled as simple coils and then as a parallel impedance circuit which has led to fundamental insight into planetary speed control and RLC combination for Schumann Resonance of 7.83 Hz. Torque and Voltage Constants and the inverse Speed Constant are calculated using three methods and all compare favorably with Newton’s Gravitational Constant. A helical resonator is referenced and Schumann’s Resonant ideal frequency is calculated and compared with others idealism. A new theory of gravity based on particle velocity selector at the poles is postulated. Two equations are presented as the needed links between Faraday’s electromagnetism and Newtonian physics. Acceleration and Deceleration of earth is explained as a centripetal governor. A new equation for planetary attraction and the attraction of atomic matter is theorized. Rotation of the earth’s electrical coil is explained in terms of the Richardson effect. Electric power transfer from the sun to the planets is proposed via Flux Transfer Events. The impact of this evolving science of electromagnetic modeling of planets will be magnified as the theory is proven, and found to be useful for future generations of engineers and scientists who seek to discover our world and other planets. 展开更多
关键词 Ampere Biot-Savart CENTRIPETAL Acceleration CENTRIPETAL GOVERNOR Dynamo EARTH Einstein-de Haas Effect Electric Field Electromagnetism Flux Transfer Events GOVERNOR Control GRAVITY Gravitational CONSTANT Helical Resonator Lenz Law Lorentz Lightning Magnetic Field Motor CONSTANT Parallel Impedance Planet SPEED Control Schumann Resonance Richardson Effect Solenoid SPEED CONSTANT Solar power System Torque CONSTANT Velocity Selector Voltage CONSTANT
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Two stages power generation test of the hot dry rock exploration and production demonstration project in the Gonghe Basin,northeastern Qinghai-Tibet plateau,China
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作者 Er-yong Zhang Dong-guang Wen +24 位作者 Gui-ling Wang Xian-peng Jin Lin-you Zhang Hai-dong Wu Wen-shi Wang Cheng-ming Ye Wei Weng Kuan Li Jin-sheng Wu Xian-chun Tang Chong-yuan Zhang Qing-da Feng Sheng Lian Li-sha Hu Gui-lin Zhu Xing-long Xie Bin Wu Dan Wang Xue Niu Zhao-xuan Niu Dong-lin Liu Hui Zhang Wen-hao Xu Shu-qing Yao Li Yang 《China Geology》 CAS CSCD 2024年第3期409-421,共13页
The Hot Dry Rock(HDR)is considered as a clean and renewable energy,poised to significantly contribute to the global energy decarbonization agenda.Many HDR projects worldwide have accumulated valuable experience in eff... The Hot Dry Rock(HDR)is considered as a clean and renewable energy,poised to significantly contribute to the global energy decarbonization agenda.Many HDR projects worldwide have accumulated valuable experience in efficient drilling and completion,reservoir construction,and fracture simulation.In 2019,China Geological Survey(CGS)initiated a demonstration project of HDR exploration and production in the Gonghe Basin,aiming to overcome the setbacks faced by HDR projects.Over the ensuing four years,the Gonghe HDR project achieved the first power generation in 2021,followed by the second power generation test in 2022.After establishing the primary well group in the initial phase,two directional wells and one branch well were drilled.Noteworthy progress was made in successfully constructing the targeted reservoir,realizing inter-well connectivity,power generation and grid connection,implementing of the real-time micro-seismic monitoring.A closed-loop technical validation of the HDR exploration and production was completed.However,many technical challenges remain in the process of HDR industrialization,such as reservoir fracture network characterization,efficient drilling and completion,multiple fracturing treatment,continuous injection and production,as well as mitigation of induced seismicity and numerical simulation technology. 展开更多
关键词 power generation Hot dry rock(HDR) Enhanced geothermal system(EGS) Genesis mechanism Gonghe Basin Directional drilling Reservoir construction Circulation test Induced seismicity Clean energy exploration engineering
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Preliminary Design, Drive-Cycle Simulation and Energy Analysis of a Hybrid Transit Bus
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作者 Roberto Capata 《Journal of Energy and Power Engineering》 2019年第6期209-228,共20页
Modern metropolises are increasingly affected by air quality problems. Transportation is one of the largest sources of several pollutants emissions, such as nitrogen oxides (NOx) and carbon monoxide (CO). Today in the... Modern metropolises are increasingly affected by air quality problems. Transportation is one of the largest sources of several pollutants emissions, such as nitrogen oxides (NOx) and carbon monoxide (CO). Today in the EU, vehicles' emissions are strictly limited by Euro 6 norm-Euro VI for heavy-duty vehicles-which is periodically upgraded. To match such limits, manufacturers are forced in developing new technologies to perform new sustainable vehicles design strategies, such as EVs and HEVs. Present work's aim is to provide the design of series-hybrid urban transportation bus, equipped with a novel thermal power unit, namely a small gas turbine, to exploit its cleaner combustion process in comparison with an ICE. The control logic is described, while the main drivetrain components are chosen, and suitable models from suppliers are selected as well. Then, some simulations of the resulting vehicle are performed on opportune drive cycles, using Advisor, a free software based on Matlab-Simulink environment, published by US' National Renewable Energy Laboratory (NREL). Two different final configurations are environmentally and economically analysed, with the thermal power unit being respectively fuelled by compressed natural gas (CNG) and liquefied petroleum gas (LPG). Both satisfy the Euro VI norms, showing a substantial emission reduction (-89% and -43% in CO and THC releases respectively) in comparison to pollutants' threshold values. 展开更多
关键词 HEV GTHV heavy-duty bus ADVISOR MICROTURBINE (MT) gas turbine (GT) CNG LPG SIMULATION drive CYCLE Euro VI WHTC emissions NOx CO THC sustainability pollution
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Review of Thermal Design of SiC Power Module for Motor Drive in Electrical Vehicle Application
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作者 Puqi Ning Xiaoshuang Hui +3 位作者 Dongrun Li Yuhui Kang Jiajun Yang Chaohui Liu 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第3期332-346,共15页
In the current vehicle electric propulsion systems,the thermal design of power modules heavily relies on empirical knowledge,making it challenging to effectively optimize irregularly arranged Pinfin structures,thereby... In the current vehicle electric propulsion systems,the thermal design of power modules heavily relies on empirical knowledge,making it challenging to effectively optimize irregularly arranged Pinfin structures,thereby limiting their performance.This paper aims to review the underlying mechanisms of how irregularly arranged Pinfins influence the thermal characteristics of power modules and introduce collaborative thermal design with DC bus capacitor and motor.Literature considers chip size,placement,coolant flow direction with the goal of reducing thermal resistance of power modules,minimizing chip junction temperature differentials,and optimizing Pinfin layouts.In the first step,algorithms should efficiently generating numerous unique irregular Pinfin layouts to enhance optimization quality.The second step is to efficiently evaluate Pinfin layouts.Simulation accuracy and speed should be ensured to improve computational efficiency.Finally,to improve overall heat dissipation effectiveness,papers establish models for capacitors,motors,to aid collaborative Pinfin optimization.These research outcomes will provide essential support for future developments in high power density motor drive for vehicles. 展开更多
关键词 Thermal design power module Pinfin Motor drive
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Power-Law Distributions in Hard Drive Behavior
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作者 Dominik Strzalka Piotr Szurlej 《Journal of Software Engineering and Applications》 2011年第12期710-717,共8页
Taking into account the fact that the computer systems, as the implementations of Turing machine, are physical devices, the paper shows considerations in which hard drive behavior will be presented in terms of statist... Taking into account the fact that the computer systems, as the implementations of Turing machine, are physical devices, the paper shows considerations in which hard drive behavior will be presented in terms of statistical mechanics. Because computer is a machine, its analysis cannot be based only on mathematical models apart of physical conditions. In the paper it will be presented a very narrow part this problem – an analysis of hard drive behavior in the context of the power-law distributions. We will focus only on four selected hard drive parameters, i.e. the rate of transfer bytes to or from the disk during the read or write, the number of pending requests to the disk and the rate of read operations. Our research was performed under the Windows operating system and this allows to make a statistical analysis for the possible occurrence of power-laws representing the lack of characteristic scale for considered processes. This property will be confirmed in all analyzed cases. A presented study can help describing the behavior of the whole computer system in terms of physics of computer processing. 展开更多
关键词 power LAWS HARD drive BEHAVIOR Performance MONITOR Windows Operating System PHYSICS of Computer Processing
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Weather-Driven Solar Power Forecasting Using D-Informer:Enhancing Predictions with Climate Variables
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作者 Chenglian Ma Rui Han +2 位作者 Zhao An Tianyu Hu Meizhu Jin 《Energy Engineering》 EI 2024年第5期1245-1261,共17页
Precise forecasting of solar power is crucial for the development of sustainable energy systems.Contemporary forecasting approaches often fail to adequately consider the crucial role of weather factors in photovoltaic... Precise forecasting of solar power is crucial for the development of sustainable energy systems.Contemporary forecasting approaches often fail to adequately consider the crucial role of weather factors in photovoltaic(PV)power generation and encounter issues such as gradient explosion or disappearance when dealing with extensive time-series data.To overcome these challenges,this research presents a cutting-edge,multi-stage forecasting method called D-Informer.This method skillfully merges the differential transformation algorithm with the Informer model,leveraging a detailed array of meteorological variables and historical PV power generation records.The D-Informer model exhibits remarkable superiority over competing models across multiple performance metrics,achieving on average a 67.64%reduction in mean squared error(MSE),a 49.58%decrease in mean absolute error(MAE),and a 43.43%reduction in root mean square error(RMSE).Moreover,it attained an R2 value as high as 0.9917 during the winter season,highlighting its precision and dependability.This significant advancement can be primarily attributed to the incorporation of a multi-head self-attention mechanism,which greatly enhances the model’s ability to identify complex interactions among diverse input variables,and the inclusion of weather variables,enriching the model’s input data and strengthening its predictive accuracy in time series analysis.Additionally,the experimental results confirm the effectiveness of the proposed approach. 展开更多
关键词 power forecasting deep learning weather-driven solar power
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PSS and SVC Controller Design using Chaos, PSO and SFL Algorithms to Enhancing the Power System Stability
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作者 Saeid Jalilzadeh Reza Noroozian +1 位作者 Mahdi Sabouri Saeid Behzadpoor 《Energy and Power Engineering》 2011年第2期87-95,共9页
In this paper, the Authors present the designing of power system stabilizer (PSS) and static var compensator (SVC) based on chaos, particle swarm optimization (PSO) and shuffled frog leaping (SFL) Algorithms has been ... In this paper, the Authors present the designing of power system stabilizer (PSS) and static var compensator (SVC) based on chaos, particle swarm optimization (PSO) and shuffled frog leaping (SFL) Algorithms has been presented to improve the power system stability. Single machine infinite bus (SMIB) system with SVC located at the terminal of generator has been considered to evaluate the proposed SVC and PSS controllers. The coefficients of PSS and SVC controller have been optimized by Chaos, PSO and SFL algorithms. Fi-nally the system with proposed controllers is simulated for the special disturbance in input power of genera-tor, and then the dynamic responses of generator have been presented. The simulation results show that the system composed with recommended controller has outstanding operation in fast damping of oscillations of power system and describes an application of Chaos, PSO and SFL algorithms to the problem of designing a Lead-Lag controller used in PSS and SVC in power system. 展开更多
关键词 power System STABILIZER (PSS) Static Var Compensator (SVC) Single Machine Infinite Bus (SMIB) CHAOS Shuffled FROG Leaping (SFL) Particle Swarm Optimization (PSO)
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商品房住宅区公共物业自治管理制度分析 以上海市水仙苑小区为例 被引量:10
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作者 顾玫 《社会》 北大核心 2005年第4期39-69,共31页
The reform of the housing system in Shanghai has unexpectedly given rise to a self-governed property owners’ collective supervisory system, primarily in the form of Property Owners’ Supervisory Council (POSC), which... The reform of the housing system in Shanghai has unexpectedly given rise to a self-governed property owners’ collective supervisory system, primarily in the form of Property Owners’ Supervisory Council (POSC), which has picked up some of the government’s administrative functions. Although this new, institutionalized management model has theoretically made democratic managerial participation at the grassroots level possible, it has brought about endless problems, overt and covert, shortly after its appearance, some of which are even alarming. A comprehensive analysis of the data collected over a long period of time has led to the conclusion that this system is a failure, attributable to the overt factor related to skills in reality and the covert “priori” factor that is masked by the former. The existence of such “priori” factor once again demonstrates the deep-rooted, traditional managerial logic: Positive operations is society need only to depend upon individuals’ unstable self-disciplined morality rather than to build a system. The current paper points out that any change in the socioeconomic structure that has long been subject to the power of politics is to inevitably incur a corresponding global structural accommodation, including politics itself. To respond to the two factors for the failure, system building in the two overlapping areas is a must. 展开更多
关键词 system possible which that RATHER global some this has model about after power The RISE form data over time SUCH NEED only than and two to of
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Application of Power Electronics Converters in Renewable Energy
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作者 Tao Cheng 《Journal of Electronic Research and Application》 2024年第4期101-107,共7页
Against the backdrop of global energy shortages and increasingly severe environmental pollution,renewable energy is gradually becoming a significant direction for future energy development.Power electronics converters... Against the backdrop of global energy shortages and increasingly severe environmental pollution,renewable energy is gradually becoming a significant direction for future energy development.Power electronics converters,as the core technology for energy conversion and control,play a crucial role in enhancing the efficiency and stability of renewable energy systems.This paper explores the basic principles and functions of power electronics converters and their specific applications in photovoltaic power generation,wind power generation,and energy storage systems.Additionally,it analyzes the current innovations in high-efficiency energy conversion,multilevel conversion technology,and the application of new materials and devices.By studying these technologies,the aim is to promote the widespread application of power electronics converters in renewable energy systems and provide theoretical and technical support for achieving sustainable energy development. 展开更多
关键词 power electronics converters Renewable energy Photovoltaic power generation Wind power generation Energy storage systems High-efficiency energy conversion Multilevel conversion New materials New devices
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