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Efficiency and Effectiveness Method versus ε-NTU Method with Application in Finned Flat Tube Compact Heat Exchanger with Water-Ethylene Glycol as Nanofluid Base of Iron Oxide Nanoparticles
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作者 Élcio Nogueira 《Journal of Materials Science and Chemical Engineering》 2022年第2期1-17,共17页
This work aims to establish comparisons between two models used for the performance of heat exchangers. The chosen system, in this case, consists of a heat exchanger used in automotive radiators flat finned tube type.... This work aims to establish comparisons between two models used for the performance of heat exchangers. The chosen system, in this case, consists of a heat exchanger used in automotive radiators flat finned tube type. Water and ethylene glycol compound as base fluid and volume fractions of iron oxide nanoparticles (Fe<sub>3</sub>O<sub>4</sub>) are used as a refrigerant. The quantities determined in this work are the nanofluid exit temperature, the air exit temperature, the absolute error between the models for heat transfer rate, and Effectiveness. The quantities that constitute parameters, independent variables, are the airflow, represented by the Reynolds number, and the iron oxide volume fraction. Ethylene Glycol 50% compound has slightly better thermal performance than pure water and reduces the reactive effect of water on the environment, increasing the average life of the equipment. The absolute relative error between the models is less than 20% and presents maximum values with the increase of the nanoparticle volume fraction and growth in the Reynolds number for the air. 展开更多
关键词 efficiency and effectiveness Method ε-NTU Method Compact Heat Exchanger Iron Oxid Nanoparticles NANOFLUID
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Temperature Effects on Information Capacity and Energy Efficiency of Hodgkin-Huxley Neuron
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作者 王龙飞 贾斐 +2 位作者 刘效治 宋亚磊 俞连春 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第10期166-169,共4页
Recent experimental and theoretical studies show that energy efficiency, which measures the amount of infor- mation processed by a neuron with per unit of energy consumption, plays an important role in the evolution o... Recent experimental and theoretical studies show that energy efficiency, which measures the amount of infor- mation processed by a neuron with per unit of energy consumption, plays an important role in the evolution of neural systems. Here we calculate the information rates and energy efficieneies of the Hodgkin-Huxley (HH) neuron model at different temperatures in a noisy environment. It is found that both the information rate and energy efficiency are maximized by certain temperatures. Though the information rate and energy efficiency cannot be maximized simultaneously, the neuron holds a high information processing capacity at the tempera- ture corresponding to the maximal energy efficiency. Our results support the idea that the energy efficiency is a selective pressure that influences the evolution of nervous systems. 展开更多
关键词 Temperature effects on Information Capacity and Energy efficiency of Hodgkin-Huxley Neuron AP
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Analysis Criteria for Defense Expenditure Performance - Economy, Efficiency, and Effectiveness
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作者 Ling Yang He Gui 《Proceedings of Business and Economic Studies》 2021年第5期117-123,共7页
Based on the analysis of public expenditure performance,this article discusses the economy,efficiency,and effectiveness of defense expenditure performance,explains the relationship of the three,and emphasizes their un... Based on the analysis of public expenditure performance,this article discusses the economy,efficiency,and effectiveness of defense expenditure performance,explains the relationship of the three,and emphasizes their unity,interaction,and priority.The defense expenditure performance evaluation system,which is a comprehensive assessment of processes and results,is put forward along with the unification of economy,efficiency,and effectiveness.This system can be used to analyze whether the allocation and use of defense funds have achieved the strategic objectives of the Department of Defense. 展开更多
关键词 Defense expenditure performance ECONOMY efficiency and effectiveness
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THE CURATIVE EFFECT OF HIGH EFFICIENCY HEMODIALYSIS AND THE GRADIENT CHANGE OF PLASMA OSMOTIC PRESSURE(Report of 27 Cases)
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《Chinese Journal of Biomedical Engineering(English Edition)》 1996年第1期25-29,共5页
THECURATIVEEFFECTOFHIGHEFFICIENCYHEMODIALYSISANDTHEGRADIENTCHANGEOFPLASMAOSMOTICPRESSURE(Reportof27Cases)Che... THECURATIVEEFFECTOFHIGHEFFICIENCYHEMODIALYSISANDTHEGRADIENTCHANGEOFPLASMAOSMOTICPRESSURE(Reportof27Cases)ChenHuaji(CentralHos... 展开更多
关键词 Report of 27 Cases THE CURATIVE effect OF HIGH efficiency HEMODIALYSIS AND THE GRADIENT CHANGE OF PLASMA OSMOTIC PRESSURE
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Evaluation of Control Effects against Sugarcane Pests:A New Sustained-release and Long-lasting Pesticide and Convenient and Efficient Pesticide Application Technology 被引量:1
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作者 Li Wenfeng Pu Chunhua +5 位作者 Zhang Rongyue Yin Jiong Luo Zhiming Shan Hongli Wang Xiaoyan Huang Yingkun 《Plant Diseases and Pests》 CAS 2017年第5期11-14,共4页
[Objective]The paper was to screen a new ideal sustained-release,long-lasting and low-toxic pesticide and convenient and efficient pesticide application technology for controlling Ceratovacuna lanigera and Baliathrips... [Objective]The paper was to screen a new ideal sustained-release,long-lasting and low-toxic pesticide and convenient and efficient pesticide application technology for controlling Ceratovacuna lanigera and Baliathrips serratus. [Method]2% Imidacloprid GR were selected and applied in the soil for field efficacy trial. [Result] The optimum dosage of 2% imidacloprid GR was 30 kg/hm^2( active ingredient 600 g),which can be mixed with fertilizer( 30 kg pesticide and 40-80 kg fertilizer per hm^2) once combined with sugarcane planting management or big ridging during February and June. The control effects against C. lanigera and B. serratus could be more than 98. 2% and 81. 1%,respectively. The actual yield and sugar content in various pesticide treatments were increased by 33 390 kg/hm^2 and 6. 6% respectively compared to blank control. [Conclusion]2% imidacloprid GR has good control effects on C. lanigera and B. serratus. It is a new pesticide with ideal sustained-release,long-lasting and low-toxin effects against C. lanigera and B. serratus. Therefore,it could be used alternatively with other pesticides,to delay production and development of drug resistance. 展开更多
关键词 Sustained-release and long-lasting pesticide Convenient and efficient pesticide application Sugarcane pests Control effect evaluation
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What Drives China’s Transformational Growth:Technology,Efficiency or Factor Cost?
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作者 何小钢 张宁 《China Economist》 2015年第5期4-18,共15页
关键词 growth transformation transformational growth technological progress effect factor price adjustment effect effect of efficiency gains
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Asymmetric dynamic phase holographic grating in nematic liquid crystal
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作者 任常愚 石宏新 +3 位作者 艾延宝 尹向宝 王丰 丁红伟 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期105-109,共5页
A new scheme for recording a dynamic phase grating with an asymmetric profile in C60-doped homeotropically aligned nematic liquid crystal(NLC) was presented.An oblique incidence beam was used to record the thin asym... A new scheme for recording a dynamic phase grating with an asymmetric profile in C60-doped homeotropically aligned nematic liquid crystal(NLC) was presented.An oblique incidence beam was used to record the thin asymmetric dynamic phase holographic grating.The diffraction efficiency we achieved is more than 40%,exceeding the theoretical limit for symmetric profile gratings.Both facts can be explained by assuming that a grating with an asymmetric saw-tooth profile is formed in the NLC.Finally,physical mechanism and mathematical model for characterizing the asymmetric phase holographic grating were presented,based on the photo-refractive-like(PR-like) effect. 展开更多
关键词 nematic liquid crystal asymmetric phase grating diffraction efficiency photorefractive effect
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Gamma Spectrometry of Inhomogeneous Samples Using Peak-Ratio Method
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作者 Thomas M. Semkow Liang T. Chu Adam G. Burn 《Journal of Applied Mathematics and Physics》 2021年第11期2641-2659,共19页
In gamma spectrometry of voluminous samples, inhomogeneous distribution of radioactivity caused by the presence of hot particles can create significant Bias in the results of activity determinations. We developed a no... In gamma spectrometry of voluminous samples, inhomogeneous distribution of radioactivity caused by the presence of hot particles can create significant Bias in the results of activity determinations. We developed a novel method to reduce this Bias using the gamma-peak ratio. We show that the peak area ratio of two gamma peaks of different energies, emitted by the same radionuclide, is a sensitive measure of emitting source location and thus the inhomogeneity. A new calibration formula was then derived for true gamma efficiency <em>p<sub>i</sub></em> as a function of efficiency ratio <em>p<sub>i</sub></em>/<em>p<sub>j</sub></em> of two peaks. This approach was verified by Monte Carlo simulations for a sample of 1-L volume containing from 1 up to 2048 of hot particles randomly distributed in a soil matrix. A <sup>152</sup>Eu radionuclide was selected for calculations and we used various combinations of two gamma spectral peaks selected from three gamma energies of 121.8, 344.3, and 1408.0 keV. This new method is shown to reduce the Bias range and Bias standard deviation by several times when compared with the traditional homogeneous calibration applied to measuring hot particles. The method is independent of the number, location, and distribution of hot particles in the samples, and can be applied to a mixture of radionuclides. It complements our previous calibration model based on the peak-to-total ratio. 展开更多
关键词 Monte Carlo Simulation Gamma Attenuation Hot Particle effective Peak efficiency Signal Detection Theory
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Influence of Structure Parameters on Performance of the Thermoelectric Module
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作者 杜群贵 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第3期464-468,共5页
A numerical model of thermoelectric module (TEM) is created by academic analysis,and the impacts of the resistance ratio and thermoelement size on the output power and thermoelectric efficiency of the TEM are analyz... A numerical model of thermoelectric module (TEM) is created by academic analysis,and the impacts of the resistance ratio and thermoelement size on the output power and thermoelectric efficiency of the TEM are analyzed by the MATLAB numerical calculation.The numerical model is validated by the ANSYS thermal,electrical,and structural coupling simulation.The effects of the variable physical property parameters and contact effect on the output power and thermoelectric efficiency are evaluated,and the concept of aspect ratio optimal domain is proposed,which provides a new design approach for the TEM. 展开更多
关键词 thermoelectric module (TEM) thermoelement contact effect variable physical property parameters output power thermoelectric efficiency
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Effect of correcting near-wall forces on nanoparticle transport in a microchannel 被引量:2
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作者 S.Andarwa H.Basirat Tabrizi G.Ahmadi 《Particuology》 SCIE EI CAS CSCD 2014年第5期84-90,共7页
This paper studies the importance of corrections that account for the presence of walls on the forces act- ing on nanoparticles during their transport in microchannels.Theoretical and experimental investigations have ... This paper studies the importance of corrections that account for the presence of walls on the forces act- ing on nanoparticles during their transport in microchannels.Theoretical and experimental investigations have reported anisotropic and hindered motion of nanoparticles near a microchannel wall. To investigate the influence of the near-wall effects, various conditions were examined. In particular, computer simu- lations were performed with and without the near-wall correction of forces. The corresponding capture efficiency and the average penetration of the captured nanoparticles were compared, and the importance of the near-wall corrections was assessed. Effects were evaluated for the nanoparticle diameter, the chan- nel width, the channel length, and the pressure gradient. The results indicate that the inclusion of wall effects is crucial for the analysis of nanoparticle transport in microchannels. 展开更多
关键词 Nanoparticle Microchannel Wall-presence effect Capture efficiency Hindered diffusion
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Self-propulsion of a three-dimensional flapping flexible plate 被引量:5
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作者 唐超 陆夕云 《Journal of Hydrodynamics》 SCIE EI CSCD 2016年第1期1-9,共9页
The self-propulsion of a 3-D flapping flexible plate in a stationary fluid is numerically studied by an immersed boundarylattice Boltzmann method for the fluid flow and a finite element method for the plate motion. Wh... The self-propulsion of a 3-D flapping flexible plate in a stationary fluid is numerically studied by an immersed boundarylattice Boltzmann method for the fluid flow and a finite element method for the plate motion. When the leading-edge of the plate is forced to heave sinusoidally, the entire plate starts to move freely as a result of the fluid-structure interaction. Based on our simulation and analysis on the dynamical behaviors of the flapping flexible plate, we have found that the effect of plate aspect ratio on its propulsive properties can be divided into three typical regimes which are related to the plate flexibility, i.e. stiff, medium flexible, and more flexible regime. It is also identified that a suitable structure flexibility, corresponding to the medium flexible regime, can improve the propulsive speed and efficiency. The wake behind the flapping plate is investigated for several aspect ratios to demonstrate some typical vortical structures. The results obtained in this study can provide some physical insights into the understanding of the propulsive mechanisms in the flapping-based locomotion. 展开更多
关键词 self-propulsion flapping-based locomotion flapping flexible plate flexibility effect propulsive efficiency
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Municipal solid waste management in Dalian: practices and challenges 被引量:1
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作者 Xinbei WANG Yong GENG 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2012年第4期540-548,共9页
The fast growing of urban areas in developing countries has brought serious problems on municipal solid waste (MSW) management. It will be rational to adopt an integrated approach to deal with such a challenge so th... The fast growing of urban areas in developing countries has brought serious problems on municipal solid waste (MSW) management. It will be rational to adopt an integrated approach to deal with such a challenge so that the overall eco-efficiency of MSW management could be improved. To better examine how attributes of integrated MSW management are being interpreted and put into practice, and to explore what changes should be made to improve the application of integrated MSW management, we employ a case study method so that lessons learned could be used to inform initiatives in other cities and the potential solution may offer feasible strategies. The case study city is Dalian, a typical seaport city with fast growing rate in economy. The outcomes of this case study show us that fragmented management structure, ineffective and inefficient enforcement of relevant regulations, backward technologies, limited financial resources and lack of public participation are main barriers for the implementation of integrated MSW management. Consequently, in order to overcome these barriers, we propose an integrated management framework on MSW management, aiming to maximize the overall eco-efficiency of MSW management. 展开更多
关键词 municipal solid waste (MSW) management 3R principles CHALLENGES ECO-efficiency effective and efficient enforcement
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