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Study on Comprehensive Efficiency Evaluation of Rural Power Grid under Rural Revitalization Strategy Considering Regional Differences
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作者 Huiru Zhao Manyu Yao +3 位作者 Zhenqi Bai Yue Zhang Zhihua Ding Zhenda Hu 《Energy Engineering》 EI 2023年第10期2211-2231,共21页
As an essential infrastructure,the rural power grid is vital in promoting agricultural and rural carbon sequestration and improving rural energy electrification.It is necessary to carry out in-depth research on its co... As an essential infrastructure,the rural power grid is vital in promoting agricultural and rural carbon sequestration and improving rural energy electrification.It is necessary to carry out in-depth research on its comprehensive efficiency.Based on the requirements of“double carbon”and rural revitalization strategy for the rural Power Grid,this paper focuses on the modernization and low-carbon transformation of the rural Power Grid.It constructs an input-output index system for the investment efficiency of the rural Power Grid in China under the new situation.It uses the primary data of the rural Power Grid of 30 prefecture-level cities in China from 2019 to 2021 to evaluate the investment efficiency of the rural Power Grid in China through a three-stage DEA model.The empirical results show that:considering the regional differences,the comprehensive efficiency of the rural Power Grid in backward areas is significantly improved;that is,the three-stage DEA method can more objectively evaluate the comprehensive efficiency of the rural Power Grid.In the context of the continued promotion of the rural revitalization strategy,to improve the comprehensive efficiency of the rural Power Grid,it is necessary to improve the technical level of the rural Power Grid further and appropriately expand the scale of investment in the rural Power Grid. 展开更多
关键词 Regional difference rural revitalization rural power grid three-stage DEA efficiency of investment
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Effect of building energy efficiency standards on carbon emission efficiency in commercial buildings
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作者 Xia Wang Qi Ye +1 位作者 Yan Du Mao Zhou 《Chinese Journal of Population,Resources and Environment》 2024年第3期250-257,共8页
The building sector plays a crucial role in the worldwide shift toward achieving net-zero emissions.Building energy efficiency standards(BEESs)are highly effective policies for reducing carbon emissions.Therefore,expl... The building sector plays a crucial role in the worldwide shift toward achieving net-zero emissions.Building energy efficiency standards(BEESs)are highly effective policies for reducing carbon emissions.Therefore,exploring the provincial variations in carbon emission efficiency(CEE)in the building sector and identifying the effect of BEESs on CEE is crucial.This study focuses on commercial buildings in China and applies a difference in differences model to evaluate the impact of BEESs on the CEE of commercial buildings.The slacks-based measure–data envelopment analysis model is employed to assess the CEE of commercial buildings in 30 Chinese provinces from 2000 to 2019.Furthermore,heterogeneous tests are used to explore how climate characteristics and economic conditions affect the efficiency of BEESs.The results indicate that BEESs positively influence the CEE of commercial buildings.Specifically,a 1%increase in the intensity of BEESs causes a 0.1484%increase in the CEE of commercial buildings.Moreover,the impact of BEESs is particularly pronounced in the southern and western provinces.This study provides valuable scientific evidence for governments to enhance BEESs implementation. 展开更多
关键词 Commercial buildings Carbon emissions efficiency Building energy efficiency standards slack-based measure–data development analysis difference in differences
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Differences in the Efficiency of Potassium(K) Uptake and Use in Five Apple Rootstock Genotypes 被引量:4
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作者 CHANG Cong LI Chao +3 位作者 LI Cui-ying KANG Xiao-yu ZOU Yang-jun MA Feng-wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第9期1934-1942,共9页
Plants that grow well while accumulating and transporting less potassium(K) perform better than more-sensitive plants when under deficiency conditions, which makes low-K-input and environmentally friendly agricultur... Plants that grow well while accumulating and transporting less potassium(K) perform better than more-sensitive plants when under deficiency conditions, which makes low-K-input and environmentally friendly agriculture possible. We conducted hydroponics and sand culture experiments to evaluate the efficiency of various apple(Malus domestica Borkh) rootstocks in their K uptake and utilization. Five genotypes were selected which are widely used in China- M. hupehensis Rehd, M. prunifolia Borkh, M. robusta Rehd, M. sieversii Roem, and M. rockii Rehd. Plant heights, root and shoot dry weights, and K concentrations were recorded. These genotypes differed markedly in dry weights, absolute and relative K concentrations, absolute and relative K accumulations, and their K efficiency ratio under deficient K conditions. The last parameter, expressed as relative shoot dry weight, was strongly and positively correlated with the other four parameters in each genotype. Therefore, we suggest that this parameter could serve as an index when selecting K-efficient genotypes. In this study, we have determined that M. sieversiiand M. rockii are K-inefficient genotypes; M. prunifolia is K-efficient genotype; M. hupehensis and M. robusta have moderate levels of potassium efficiency. 展开更多
关键词 apple rootstock genotypes potassium efficiency genotype difference potassium uptake potassium utilization
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Mechanisms of Difference in Mn Efficiency Between Wheat and Oilseed Rape 被引量:7
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作者 FANGZHENG ZHANGFUSUO 《Pedosphere》 SCIE CAS CSCD 2000年第3期213-220,共8页
By solution culture experiment, three wheat genotypes (Ttiticum aestivum L.) and two oilseed rape genotypes (Brassica napus L.) differing in Mn efficiency under Mn-deficient conditions were used to study mechanisms of... By solution culture experiment, three wheat genotypes (Ttiticum aestivum L.) and two oilseed rape genotypes (Brassica napus L.) differing in Mn efficiency under Mn-deficient conditions were used to study mechanisms of the difference in Mn efficiency between wheat and oilseed rape. The results showed that there were significant differences in the abilities of MnIV reduction and acidification in root rhizosphere between the two species. Compared with wheat, oilseed rape had much higher reducing capacity and intensity of rhizosphere acidification under Mn-deficient conditions. Moreover, the higher ratio of functional leaves Mn/old leaves Mn in oilseed rape than in wheat was also an important factor for the different Mn efficiencies between the two species. 展开更多
关键词 genotypic difference MECHANIsM Mn efficiency oilseed rape whL
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Regional differences and threshold characters of the impact of energy use efficiency on energy scarcity in China
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作者 Min Li Kaisheng Long 《Chinese Journal of Population,Resources and Environment》 2021年第3期265-273,共9页
The improvement of the technical efficiency of energy use has been widely seen as an important way to alleviate energy scarcity.However,the energy rebound effect demonstrates the vulnerability and unsustainability of ... The improvement of the technical efficiency of energy use has been widely seen as an important way to alleviate energy scarcity.However,the energy rebound effect demonstrates the vulnerability and unsustainability of alleviating energy scarcity relying on technology.Under the background of the consistent development of energy factor market,it is of great importance to explore the paths and differences of energy source allocation constrained by technology and cost to promote the sustainable use of energy.This study analyzed the regional differences and threshold characteristics in the impact of the technical and cost efficiency of energy use on energy scarcity using the instrumental variable-two-stage least square method,based on the panel data of Chinese provinces from 2003 to 2017.The results showed that:①Technology and price were the critical forces of the technical and cost efficiency of energy use.They changed the degree of use of surplus production factors by affecting the complementary and replacement demand relationship between energy and non-energy factors.Meanwhile,the impact of energy use efficiency on energy scarcity showed regional and time features due to the different technology capabilities and different levels of market development in different regions and different time.②The alleviation of energy scarcity at the national level relied on the improvement of energy cost efficiency.At the regional level,the alleviation of energy scarcity in central China came from the improvement of the technical efficiency of energy use.However,the alleviation of energy scarcity in the eastern and western regions was due to the improvement of energy cost efficiency.③Constrained by the economic development,openness,science and technology input and the industrial development structure,the impact of the technical and cost efficiency of energy use on energy scarcity demonstrated a nonlinear feature.And structural mutation occurred after passing a specific‘inflection point’,which showed a significant threshold feature.Therefore,energy price should play an important role in energy use and it is necessary to pay attention to the regional differences and time characteristics of energy economic development to promote the sustainable development of energy resources. 展开更多
关键词 Eenergy use technical efficiency Energy cost efficiency Energy scarcity Regional difference Threshold regression
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Measurement of Grain Production Efficiency in Main Grain-producing Areas and Analysis of Inter-provincial Differences--A Study Based on Super-SBM Model and Malmquist Index
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作者 Qi Heng Su Jing-yan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2022年第2期86-96,共11页
China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-p... China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-producing areas has become the fundamental way to strengthen the grain production capacity and improve the national food security capability,and to improve the efficiency of grain production in major grain-producing areas requires empirical support.This paper used the Super SBM model and the Malmquist index to measure the grain production efficiency of the main grain-producing areas from 2001 to 2020 from both static and dynamic perspectives,and compared the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas.The results showed that from 2001 to 2020,the grain production in the main grain-producing areas was in a relatively ineffective state,and the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas were obvious.The order of grain production efficiency in different soil types was black soil region>red-yellow soil region>paddy soil region>fluvo-aquic soil region,and the order of grain production efficiency of the provinces(autonomous regions)in the main grain-producing areas was Jilin>Heilongjiang>Inner Mongolia>Jiangxi>Hunan>Sichuan>Hubei>Jiangsu>Liaoning>Henan>Anhui>Shandong>Hebei.From 2001 to 2020,the total factor productivity of grain in the main grain-producing areas increased,but due to the trade-off between the technological progress and the growth of technical efficiency,the increase in the total factor productivity of grain in the main grain-producing areas was small,and the growth mainly came from the increase of input factors in this period.The total factor productivity of grain in Hebei,Heilongjiang,Liaoning,Jilin,Inner Mongolia,Shandong,Jiangsu,Henan and Anhui increased,but the increase was small,while the total factor productivity of grain in Jiangxi,Sichuan,Hunan and Hubei provinces declined. 展开更多
关键词 main grain-producing area grain production efficiency inter-provincial difference
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Effects of Different Management Modes on Yield and Nutrient Efficiency of Ginger
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作者 郑福丽 张柏松 +4 位作者 高燕 田叶 马征 谭德水 江丽华 《Agricultural Science & Technology》 CAS 2015年第6期1222-1226,共5页
In order to establish high-yield and high-efficient cultivation technology for ginger in the central region of Shandong Province, the effects of different manage-ment modes on yield of ginger, nutrient efficiency and ... In order to establish high-yield and high-efficient cultivation technology for ginger in the central region of Shandong Province, the effects of different manage-ment modes on yield of ginger, nutrient efficiency and soil nitrate were carried out by field experiment. Four management modes were farmer convention mode, high yield and high efficiency mode, super high yield mode and super high yield and high efficiency mode, in which farmer convention mode was local farmers ’ conven-tional cropping methods, the other three management modes were optimized combi-nations of al management measures under a certain goal of increasing yield and efficiency. The results were as fol ows: ginger yield and nitrogen fertilizer efficiency under such three optimized management measures combinations as high yield and high efficiency mode, super high yield mode and super high yield and high efficien-cy mode were al higher than these of farmer convention mode, moreover, com-pared with farmer convention mode, the yield increased by 11.85%, 25.75% and 23.34%, respectively, and nitrogen fertilizer efficiency increased by 47.94%, 11.24%and 33.14%, respectively. Thereinto, the yield under super high yield mode were the greatest,and nitrogen fertilizer efficiency under high yield and high efficiency mode was the highest. 展开更多
关键词 different management modes GINGER YIELD Nutrient efficiency
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An Efficient and Lightweight YOLOv8s Strawberry Maturity Detection Model
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作者 Yiming Cheng Guohao Feng Chunchang Zhang 《Journal of Agricultural Science and Technology(A)》 2024年第2期46-66,共21页
The manual picking of strawberries is inefficient and costly,limiting scalability and economic benefits.Mechanizing this process reduces labor demands,improves working conditions,and modernizes the strawberry industry... The manual picking of strawberries is inefficient and costly,limiting scalability and economic benefits.Mechanizing this process reduces labor demands,improves working conditions,and modernizes the strawberry industry.Target detection technology,crucial for mechanized picking,must accurately determine strawberry maturity.This study presents an enhanced YOLOv8s model addressing current machine learning issues like accuracy,parameters,and complexity.The improved model replaces the Bottleneck structure in C2f with the FasterNet network,integrates an efficient multi-scale attention mechanism,and uses the Ghost module in the backbone to reduce computational load while maintaining performance.It also introduces Wise-IoU for bounding box regression loss,improving recognition accuracy.The YOLOv8s-FEGW model achieves a 93.8%mAP in detecting strawberry ripeness,with significant reductions in parameters(36.8%),complexity(34.6%),and model size(37.7%),alongside a 12.7% Frames Per Second(FPS)boost.These enhancements result in excellent detection capabilities,supporting agricultural automation and intelligence. 展开更多
关键词 Automation equipment artificial intelligence efficient and lightweight YOLOv8s
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Cultural Differences Between China and the West Behind“neijuan”
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作者 HUANG Wen-xi 《Journal of Literature and Art Studies》 2023年第2期104-109,共6页
Over recent years,our society has plunged into the phenomenon of“neijuan”(in English“involution”,a kind of meaningless competition).And it even becomes a social dilemma that many people are forced to make more eff... Over recent years,our society has plunged into the phenomenon of“neijuan”(in English“involution”,a kind of meaningless competition).And it even becomes a social dilemma that many people are forced to make more efforts to compete for limited social resources.This phenomenon has,of course,attracted the attention of many researchers.There are many researches about“neijuan”varying from its popularity reasons and its trend to its application,but there is very little research about the cultural differences between China and the West behind this phenomenon.Therefore,based on Hofstede’s cultural dimensions theory,this paper analyses the different manifestations of“neijuan”in China and the West and explores the cultural differences between the two. 展开更多
关键词 neijuan Hofstede’s cultural dimensions theory cultural differences
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Differential response of root morphology to potassium deficient stress among rice genotypes varying in potassium efficiency 被引量:36
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作者 Yan-bo JIA Xiao-e YANG +1 位作者 Ying FENG Ghulam JILANI 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第5期427-434,共8页
Disparity in the root morphology of six rice(Oryza sativa L.) genotypes varying in potassium(K) efficiency was studied with three K levels:5 mg/L(low),10 mg/L(moderate) and 40 mg/L(adequate) in hydroponic culture. Mor... Disparity in the root morphology of six rice(Oryza sativa L.) genotypes varying in potassium(K) efficiency was studied with three K levels:5 mg/L(low),10 mg/L(moderate) and 40 mg/L(adequate) in hydroponic culture. Morphological parameters included root length,surface area,volume and count of lateral roots,as well as fine(diameter<0.2 mm) and thick(diameter>0.2 mm) roots. The results indicate that the root growth of all genotypes was reduced under low K,but moderate K deficiency increased the root length of the efficient genotypes. At deficient and moderate K levels,all the efficient rice genotypes developed more fine roots(diameter<0.2 mm) than the inefficient ones. Both fine root count and root surface area were found to be the best parameters to portray K stress in rice. In accordance with the root morphology,higher K concentrations were noted in shoots of the efficient genotypes when grown at moderate and deficient K levels,indicating that root morphology parameters are involved in root uptake for K and in the translocation of K up to shoots. K deficiency affected not only the root morphology,but also the root ultra-structure. The roots of high-efficient genotypes had stronger tolerance to K deficient stress for root membrane damage,and could maintain the developed root architecture to adapt to the low K growth medium. 展开更多
关键词 Genotypic difference Potassium (K) efficiency Root surface area Fine root development Root cell utra-structure
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Effect of Supplied P Levels on Rice Growth and Uptake of P and Zn in Different P-Efficiency Genotypes 被引量:2
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作者 Guo Zai-hua HE Li-yuan Xu Cai-guo 《Rice science》 SCIE 2005年第2期119-124,共6页
A soil pot culture experiment with four supplied P levels (i.e. P30, P50, P100, P200, representing supplemental P 30, 50, 100, 200 mg/kg, respectively) was conducted to investigate uptake and use ability to P and Zn... A soil pot culture experiment with four supplied P levels (i.e. P30, P50, P100, P200, representing supplemental P 30, 50, 100, 200 mg/kg, respectively) was conducted to investigate uptake and use ability to P and Zn in the rice genotypes with different P-efficiency, of which rice genotypes 508, 99011, 580, 99112 were Iow-P tolerant and 99056, 99012 were Iow-P sensitive. Low-P tolerant rice 580 and 99011 absorbed more P than the others, and rice genotype 580 had stronger uptake ability especially at Iow-P level such as P50 and P30. 508 could absorb considerable P, and had the lowest P percentage of shoot, indicating it had good performance in P-use efficiency. These three rice genotypes had larger biomass and less response to changed P level than rice genotype 99112, 99056 and 99012. Rice genotype 99112 showed Low-P tolerance mainly by sacrificing biomass to maintain high relative grain yield. The least amount of P absorbed by 99056 showed it had the lowest P uptake efficiency, and the highest P percentage in shoot of 99012 meant it had the lowest P use efficiency. So they two showed Iow-P sensitivity. Zn contents in shoot under P200, P100 and P50 were similar, but P30 increased Zn content in shoot significantly. The Zn contents in shoot of 99112, 99056 and 99012 were higher than those of 508, 99011 and 580, especially at tillering stage and booting stage. As for total Zn content in shoot, Low-P tolerant rice genotype 580 had the largest amount and followed by 99011 and 508, Iow-P tolerant rice genotype 99012 had the smallest amount at the three sampling stage and followed by 99056. Furthermore, P/Zn in shoot of 99012 was the highest, and that of 99056 was the smallest at the same P level. 展开更多
关键词 genotypic difference PHOsPHORUs ZINC BIOMAss use efficiency
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Efficient BTCS + CTCS Finite Difference Scheme for General Linear Second Order PDE 被引量:1
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作者 Gueye Serigne Bira Mbow Cheikh Diagana Mouhamed Fadel 《Journal of Electromagnetic Analysis and Applications》 2021年第10期135-143,共9页
This work deals with a second order linear general equation with partial derivatives for a two-variable function. It covers a wide range of applications. This equation is solved with a finite difference hybrid method:... This work deals with a second order linear general equation with partial derivatives for a two-variable function. It covers a wide range of applications. This equation is solved with a finite difference hybrid method: BTCS + CTCS. This scheme is simple, precise, and economical in terms of time and space occupancy in memory. 展开更多
关键词 Finite difference BCTs %PLUs% CTCs Usmani’s Algorithm Tridiagonal Matrix Telegraph Equation
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Collision efficiency of two nanoparticles with different diameters in Brownian coagulation
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作者 王玉明 林建忠 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第8期1019-1028,共10页
The collision efficiency of two nanoparticles with different diameters in the Brownian coagulation is investigated. The collision equations are solved to obtain the collision efficiency for the dioctyl phthalate nanop... The collision efficiency of two nanoparticles with different diameters in the Brownian coagulation is investigated. The collision equations are solved to obtain the collision efficiency for the dioctyl phthalate nanoparticle with the diameter changing from 100 nm to 750 nm in the presence of the van der Waals force and the elastic deformation force. It is found that the collision efficiency decreases as a whole with the increase of both the particle diameter and the radius ratio of two particles. There exists an abrupt increase in the collision efficiency when the particle diameter is equal to 550 nm. Finally, a new expression is presented for the collision efficiency of two nanoparticles with different diameters. 展开更多
关键词 NANOPARTICLE Brownian coagulation collision efficiency different diameters van der Waals force elastic force
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The Efficiency Droop of InGaN-Based Green LEDs with Different Superlattice Growth Temperatures on Si Substrates via Temperature-Dependent Electroluminescence
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作者 齐维靖 徐龙权 +8 位作者 莫春兰 王小兰 丁杰 王光绪 潘拴 张建立 吴小明 刘军林 江风益 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期224-227,共4页
InGaN-based green light-emitting diodes (LEDs) with different growth temperatures of superlattice grown on Si (111) substrates are investigated by temperature-dependent electroluminescence between 100 K and 350K. ... InGaN-based green light-emitting diodes (LEDs) with different growth temperatures of superlattice grown on Si (111) substrates are investigated by temperature-dependent electroluminescence between 100 K and 350K. It is observed that with the decrease of the growth temperature of the superlattice from 895℃ to 855℃, the forward voltage decreases, especially at low temperature. We presume that this is due to the existence of the larger average size of V-shaped pits, which is determined by secondary ion mass spectrometer measurements. Meanwhile, the sample with higher growth temperature of superlattice shows a severer efficiency droop at cryogenic temperatures (about 100 K-150 K). Electron overflow into p-GaN is considered to be the cause of such phenomena, which is relevant to the poorer hole injection into multiple quantum wells and the more reduced effective active volume in the active region. 展开更多
关键词 InGaN The efficiency Droop of InGaN-Based Green LEDs with different superlattice Growth Temperatures on si substrates via Temperature-Dependent Electroluminescence si
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New Color-Difference Formula Based on CIECAM97s 被引量:1
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作者 宦晖 李为 赵达尊 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期149-152,共4页
To deduce a new color difference formula based on CIE 1997 Color Appearance Model(CIECAM97s), a color space J a 1 b 1 is first constructed with color appearance descriptors J,a,b in CIECAM97s. The new f... To deduce a new color difference formula based on CIE 1997 Color Appearance Model(CIECAM97s), a color space J a 1 b 1 is first constructed with color appearance descriptors J,a,b in CIECAM97s. The new formula is then deduced in the space and named CDF CIECAM97s. The factors for lightness, chroma and hue correction in the formula are derived by linear regression according to BFD? CP data sets. It is found by statistical analysis that CDF CIECAM97s is in closer accordance with the visual assessments when compared with CMC(1∶1), CIE94 and CIE L *a *b * color difference formulae. Based on color appearance model, the new color difference formula can be used to predict color difference perception in a varity of different viewing conditions. 展开更多
关键词 CIECAM97s color difference formulae color space
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基于多目标遗传算法的8×8 S盒的优化设计方法
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作者 王永 王明月 龚建 《西南交通大学学报》 EI CSCD 北大核心 2024年第3期519-527,538,共10页
混沌系统具有非线性、伪随机性、初始值敏感等特性,为基于动力系统构造性能良好的S盒提供了基础,进一步保证了分组加密算法安全性.目前,基于混沌构造S盒的方法大多数针对单个性能指标进行优化,难以获得全面的性能提升.针对此问题,结合... 混沌系统具有非线性、伪随机性、初始值敏感等特性,为基于动力系统构造性能良好的S盒提供了基础,进一步保证了分组加密算法安全性.目前,基于混沌构造S盒的方法大多数针对单个性能指标进行优化,难以获得全面的性能提升.针对此问题,结合混沌映射与多目标遗传算法,提出了一种新的S盒设计方法.首先,利用混沌映射的特性产生初始S盒种群;然后,以S盒的非线性度和差分均匀性为优化目标,基于遗传算法框架对上述两指标进行优化.针对S盒的特点,在优化算法中引入了交换操作,设计了新的变异操作以及非支配序集计算,有效提升了S盒的非线性度和差分均匀性.实验结果表明该算法产生的S盒其差分均匀度为6,非线性度值至少为110,有效提升了S盒的综合性能. 展开更多
关键词 s 非线性度 差分均匀度 多目标遗传算法 混沌映射
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基于程函面波成像的华北克拉通岩石圈三维高分辨率S波速度结构研究
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作者 钟世军 吴建平 +2 位作者 司政亚 朱红彬 王薇 《地震学报》 CSCD 北大核心 2024年第4期578-599,共22页
利用“中国地震科学台阵探测”项目Ⅱ期和Ⅲ期的流动地震台站以及中国区域地震台网中的部分固定台站的观测资料,采用程函面波成像方法获得了华北克拉通及周边区域10—120 s周期的瑞雷面波相速度分布和高分辨率的三维S波速度结构,并基于... 利用“中国地震科学台阵探测”项目Ⅱ期和Ⅲ期的流动地震台站以及中国区域地震台网中的部分固定台站的观测资料,采用程函面波成像方法获得了华北克拉通及周边区域10—120 s周期的瑞雷面波相速度分布和高分辨率的三维S波速度结构,并基于该速度模型估算了岩石圈厚度分布。结果显示,华北克拉通内部岩石圈厚度除了存在“西厚东薄”的一级分布特征外,还存在一些更小尺度的差异,包括鄂尔多斯地块内部岩石圈“南厚北薄”、鄂尔多斯地块周缘断陷带岩石圈显著的不均匀减薄以及燕山构造带与其南侧华北平原之间的显著差异等。山西断陷带北部与南部地区上地幔浅部(<100 km)存在不同程度的低速异常,它们被中部的高速异常区所分隔。在150 km以下深度从太行山南缘向北至山西断陷北缘存在一条NNE向展布的显著低速异常带,表明上地幔浅部南北部的低速异常在深部相连。结合已有的其它成像结果,我们推测这些低速异常起源于更深处(>200 km),并与由太平洋俯冲板块的滞留脱水导致的上地幔热物质上涌和小尺度地幔对流等密切相关。燕山构造带与华北平原的岩石圈结构存在明显差异,前者遭受的岩石圈破坏改造程度明显弱于后者,张家口—渤海地震带位于这两种不同壳幔结构的过渡带,地震活动较强,我们认为深部结构和热作用的显著差异,以及青藏高原远场挤压效应的共同作用是导致该区地震活动较强的主要原因。 展开更多
关键词 华北克拉通 程函面波成像 s 波速度 低速异常 岩石圈厚度 显著差异
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On the Gender Difference of Translator's Subjectivity in Literary Translation
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作者 陈志海 董淑新 王齐 《海外英语》 2014年第22期120-122,125,共4页
Translation is an activity aimed at transferring the source language to the target language,related to many aspects involving culture,society,history and so on.The translator plays a critical role in translation pract... Translation is an activity aimed at transferring the source language to the target language,related to many aspects involving culture,society,history and so on.The translator plays a critical role in translation practice.Xu Jun considers"translator’s subjectivity should be reflected to be artistic personal consciousness in translated works."Translator’s differences in age,gender,personal traits,educational level and other aspects make translation artistry completely divergent.Therefore,translator’s subjectivity shoulders great significances on the success of literary translation,which isn’t arbitrary,out of control,must be conducted in line with essence of the original work.This paper focuses on the gender difference of translator’s subjectivity in literary translation,hoping to find a way of eliminating the influence of it in the translation work. 展开更多
关键词 translator’s sUBJECTIVITY GENDER difference androg
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基于Cross-efficiency DEA算法的区域科技资源配置效率测算研究 被引量:9
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作者 贾岩 《现代情报》 2009年第2期219-221,225,共4页
伴随信息化水平的日益提高,我国科技资源组织结构和运行效率进一步优化。然而由于我国区域经济发展的非均衡性问题,导致了我国科技资源配置的区域差异性。本文引入Cross-efficiency DEA算法,从科技资源投入、产出的视角对我国30个省、... 伴随信息化水平的日益提高,我国科技资源组织结构和运行效率进一步优化。然而由于我国区域经济发展的非均衡性问题,导致了我国科技资源配置的区域差异性。本文引入Cross-efficiency DEA算法,从科技资源投入、产出的视角对我国30个省、市、自治区对应的科技资源配置效率进行了测算。利用Cross-efficiency在群体综合评价中能够完全排序的优点,可以获得区域资源配置效率的排序结果,从而为区域科技管理提供有效的参考信息。 展开更多
关键词 cross-efficiency 数据包络分析 科技资源 资源配置效率
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基于超效率SBM模型的东北三省城市土地利用效率时空差异及影响因素 被引量:2
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作者 潘莹莹 姜博 +1 位作者 李梦珍 刘新阳 《水土保持研究》 CSCD 北大核心 2024年第1期408-416,共9页
[目的]探究东北三省城市土地利用效率时空差异及影响因素,为东北三省和其他欠发达地区的城市高质量发展和优化国土空间格局提供借鉴参考。[方法]运用超效率SBM模型、非参数核密度估计以及Tobit回归模型对2010—2020年东北三省城市土地... [目的]探究东北三省城市土地利用效率时空差异及影响因素,为东北三省和其他欠发达地区的城市高质量发展和优化国土空间格局提供借鉴参考。[方法]运用超效率SBM模型、非参数核密度估计以及Tobit回归模型对2010—2020年东北三省城市土地利用效率时空差异及影响因素进行分析。[结果](1)从时间演变特征来看,东北三省城市土地利用效率均值呈显著上升趋势,但整体水平不高;从空间演变特征来看,区域差异显著,低值区城市数量大幅度减少,高值区城市增多,高值区城市分布范围从黑龙江覆盖至东北三省全域。(2)从时序动态演进特征来看,研究期间不同时段内三大省份城市土地利用效率的极化程度、效率差异和发展水平都呈现出不同的动态演进特征。(3)从影响因素分析来看,各变量对辽宁、吉林、黑龙江三省城市土地利用效率的影响程度和作用方向有所差异,人力资本、科教支出、经济发展水平、对外开放程度、产业结构、交通基础设施和城镇化率具有促进作用,环境规制具有抑制作用。[结论]实现城市高质量发展和土地集约高效利用,各城市应因地制宜、因城施策,从刺激经济增长、产业结构优化升级、优化营商环境、做好人才和资金引进工作等方面系统推进。 展开更多
关键词 城市土地利用效率 时空差异 super-sBM 东北三省
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