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Secure Computation Efficiency Resource Allocation for Massive MIMO-Enabled Mobile Edge Computing Networks
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作者 Sun Gangcan Sun Jiwei +3 位作者 HaoWanming Zhu Zhengyu Ji Xiang Zhou Yiqing 《China Communications》 SCIE CSCD 2024年第11期150-162,共13页
In this article,the secure computation efficiency(SCE)problem is studied in a massive multipleinput multiple-output(mMIMO)-assisted mobile edge computing(MEC)network.We first derive the secure transmission rate based ... In this article,the secure computation efficiency(SCE)problem is studied in a massive multipleinput multiple-output(mMIMO)-assisted mobile edge computing(MEC)network.We first derive the secure transmission rate based on the mMIMO under imperfect channel state information.Based on this,the SCE maximization problem is formulated by jointly optimizing the local computation frequency,the offloading time,the downloading time,the users and the base station transmit power.Due to its difficulty to directly solve the formulated problem,we first transform the fractional objective function into the subtractive form one via the dinkelbach method.Next,the original problem is transformed into a convex one by applying the successive convex approximation technique,and an iteration algorithm is proposed to obtain the solutions.Finally,the stimulations are conducted to show that the performance of the proposed schemes is superior to that of the other schemes. 展开更多
关键词 EAVESDROPPING massive multiple input multiple output mobile edge computing partial offloading secure computation efficiency
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Difference of Nitrogen Uptake and Use Efficiency in Conventional Indica Rice Cultivars with Different Nitrogen Use Efficiency for Grain Output 被引量:3
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作者 周娟 李进前 +4 位作者 张彪 张传胜 张岳芳 王余龙 董桂春 《Agricultural Science & Technology》 CAS 2008年第6期68-73,141,共7页
[Objective] The study aimed to confirm difference of nitrogen uptake and used efficiency with different nitrogen use efficiency for grain output (NUEg) types of indica rice.[Method] 88 and 122 conventional indica rice... [Objective] The study aimed to confirm difference of nitrogen uptake and used efficiency with different nitrogen use efficiency for grain output (NUEg) types of indica rice.[Method] 88 and 122 conventional indica rice cultivars were solution-cultured in 2001 and 2002, respectively. Dry matter weight (including root system, culm and sheath, leaves, panicle), nitrogen content of different organs, yield and its components were measured. The tested rice cultivars were classified into 6 types (i.e. A, B, C, D, E and F, A was the lowest, and F was the highest) based on their NUEg level by the MinSSw method.[Result](1)Difference of NUEg of the cultivars used in this study were very large; (2) No significant difference of N content at heading stage was observed among different NUEg types of indica rice. In the cultivars with higher NUEg, however, N content in leaf, stem-sheath and entire rice plant were lower at mature stage. (3)Cultivars with higher NUEg were characterized with lower N uptake before heading and at mature stage; (4) Cultivars with higher NUEg were characterized with higher N use efficiency in biomass production and harvest index. [Conclusion] The cultivars with higher NUEg showed lower N uptake and N content, while nitrogen use efficiency was higher. 展开更多
关键词 Conventional INDICA rice CULTIVARS NITROGEN content for grain output NITROGEN UPTAKE NITROGEN use efficiency
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A Study on Input-Output Efficiency of Citrus in Jiangxi Province
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作者 Yu ZHONG 《Asian Agricultural Research》 2018年第1期10-15,共6页
This paper analyzes the citrus input-output efficiency by using the DEA-Malmquist productivity index methods based on the data of six counties in Jiangxi Province from 2010 to 2013.The result shows that TFP of Jiangxi... This paper analyzes the citrus input-output efficiency by using the DEA-Malmquist productivity index methods based on the data of six counties in Jiangxi Province from 2010 to 2013.The result shows that TFP of Jiangxi citrus is at low level overall,but the development is rapid.Technological progress is the driving force to promote productivity growth.Based on the static analysis study of six counties in 2013,it is found that the available input factors on the whole are in an ideal condition,and the citrus input factors in a few counties are redundant.Therefore,according to the results,the following policy recommendations are proposed:speeding up the intensive production of citrus in Jiangxi Province,to maximize the scale effect;adjusting the input ratio of various factors of production,so as to improve the citrus input-output efficiency. 展开更多
关键词 input-output efficiency Total factor productivity Citrus industry Technological progress
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Prediction of efficient outputs based on GM(1,N) model and weak DEA efficiency 被引量:2
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作者 Jiefang Wang Sifeng Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第6期933-939,共7页
This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient ou... This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient outputs.The increased outputs are solved by linear programming using data envelopment analysis efficiency theories,wherein a new sample is introduced whose inputs are equal to the budget in the issue No.n + 1 and outputs are forecasted by the GM(1,N) model.The shortcoming in the existing methods that the forecasted efficient outputs may be less than the possible actual outputs according to developing trends of input-output rate in the periods of pre-n is overcome.The new prediction method provides decision-makers with more decisionmaking information,and the initial conditions are easy to be given. 展开更多
关键词 efficient outputs GM(1 N) model data envelopment analysis(DEA) weak DEA efficiency prediction.
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Promoting Balance in Output Efficiencies for Cross-Efficiency Evaluation in Data Envelopment Analysis
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作者 Jin-Xiao Chen 《Journal of Applied Mathematics and Physics》 2019年第3期664-685,共22页
Cross-efficiency evaluation is recognized as an effective way of efficiency assessment for a set of decision making units (DMUs) in the framework of data envelopment analysis (DEA). It has been generally suggested tha... Cross-efficiency evaluation is recognized as an effective way of efficiency assessment for a set of decision making units (DMUs) in the framework of data envelopment analysis (DEA). It has been generally suggested that secondary goals be introduced for cross-efficiency evaluation owing to the non-uniqueness of optimal solutions in self-evaluation. This paper develops a variety of secondary goals in the spirit of promoting balance in the output efficiencies of the DMU under evaluation. The proposed models attempt to make each output contribute as equally as possible to the self-evaluated efficiency. In this way, the weight flexibility can for one thing be reduced by the introduced secondary goals with selections from alternate optimal solutions, in addition to counting on the dilution of flexibility in the subsequent peer-evaluation. The proposed approach might be applicable to evaluation problems in which multiple outputs are considered important and balance is encouraged to put all dimensions into sufficient use. The effectiveness of the proposed approach and its comparisons with some relevant secondary goals are illustrated empirically using numerical examples. 展开更多
关键词 Data Envelopment Analysis Cross-efficiency Evaluation SECONDARY GOAL BALANCE output efficiency
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Assessing Asian Economies Renewable Energy Consumption Efficiency Using DEA with Undesirable Output
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作者 Chia-Nan Wang Ngoc-Ai-Thy Nguyen +1 位作者 Thanh-Tuan Dang Jing-Wein Wang 《Computer Systems Science & Engineering》 SCIE EI 2022年第10期347-362,共16页
Along with vast non-fossil potential and significant expertise,there is a question of whether Asian nations are attaining efficient consumption and exploitation of renewable resources.From this perspective,the paper a... Along with vast non-fossil potential and significant expertise,there is a question of whether Asian nations are attaining efficient consumption and exploitation of renewable resources.From this perspective,the paper aims to evaluate the efficiency of 14 potential Asia countries in renewable energy consumption during the six-year periods(2014-2019).In analyzing the performance of the renewable energy sector,the data envelopment analysis(DEA)with an undesirable output model approach has been widely utilized to measure the efficiency of peer units compared with the best practice frontier.We consider four inputs and two outputs to a DEA-based efficiency model.Labor force,total energy consumption,share of renewable energy,and total renewable energy capacity are inputs.The outputs consist of CO_(2)emissions as an undesirable output and gross domestic product as a desirable output.The results show that United Arab Emirates,Saudi Arabia,Japan,and South Korea consistently outperform in the evaluation,achieving perfect efficiency scores during the research period.Uzbekistan is found to have the lowest average efficiency of renewable energy utilization. 展开更多
关键词 ASIA renewable energy efficiency FRONTIER data envelopment analysis bad output
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Input and output efficiency of urban agglomerations in China using DEA multi-stage model
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作者 LI Qiu-ying 《Ecological Economy》 2019年第2期95-100,共6页
In this study, we apply the data envelopment analysis(DEA) model to quantitatively measure the input and output efficiency of 19 urban agglomerations in China from 2011 to 2016. The results show that the input and out... In this study, we apply the data envelopment analysis(DEA) model to quantitatively measure the input and output efficiency of 19 urban agglomerations in China from 2011 to 2016. The results show that the input and output efficiency of urban agglomerations is relatively not high, only a small number of that reach the optimal DEA efficiency. It is clearly revealed that there are the regions from the east that presents the better performance, followed by regions from the central and the west. The peer counts show that Zhusanjiao is taken into account 12 times which shows the importance here of the Zhusanjiao model.Considering the values for radial movements and the slack movements, respective urban agglomeration has their improving orientation towards the capital slack, the labor slack or the land slack. It offers a scientific decision-making of for healthy urbanization and high quality development. 展开更多
关键词 INPUT and output efficiency urban agglomerations MULTI-STAGE DEA
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Urban Water Resource Utilization Efficiency in China 被引量:14
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作者 SHI Tiange ZHANG Xiaolei +1 位作者 DU Hongru SHI Hui 《Chinese Geographical Science》 SCIE CSCD 2015年第6期684-697,共14页
The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis ... The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis (SBM-DEA) has been widely used in energy efficiency and environmental efficiency analyses in recent years. Based on this model, data from 316 cities were examined and a category method was employed involving three different sorting techniques to empirically evaluate the efficiency of urban water re- source utilization in China between 2000 and 2012. The overall efficiency (OE) of urban water resource utilization in China was initially low, but has improved over the past decade. The scale efficiency (SE) was higher than the pure technological efficiency (PTE); PTE is a major determining factor of OE, and has had an increasingly significant effect. The efficiency of water resource utilization varied ac- cording to the region, urban scale, and economic function. The OE score for the eastern China was higher than for the rest of the region, and the OE score for the western China was higher than for the central China. The OE score for urban water resource utilization has improved with urban expansion, except in the case of small cities. The SE showed an inverted U-shaped' trend with increasing urban expansion. The OE of urban water utilization in comprehensive functional cities was greater than in economic specialization cities, and was greater in heavy industry specialization cities than in other specialization cities. This study contributes to the field of urban water resource management by examining variations in efficiency with urban ~ezle 展开更多
关键词 urban water resource utilization efficiency urban scale undesirable outputs a slacks-based measure for data envelopmentanalysis (SBM-DEA) China
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Measuring Chinese Marine Environmental Efficiency:A Spatiotemporal Pattern Analysis 被引量:3
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作者 DI Qianbin ZHENG Jinhua YU Zhe 《Chinese Geographical Science》 SCIE CSCD 2018年第5期823-835,共13页
Environmental efficiency standards are often used to evaluate the costs of oceanic economic development. A variety of statistical analyses were applied in this study to quantify the marine environmental efficiency of ... Environmental efficiency standards are often used to evaluate the costs of oceanic economic development. A variety of statistical analyses were applied in this study to quantify the marine environmental efficiency of 11 Chinese coastal provinces and municipalities between 2000 and 2014. Results initially reveal that environmental efficiency measures that incorporate undesirable outputs are more consistent with real production conditions and thus the use of marine economic and environmental efficiencies supplement and complement one another. Second, overall marine environmental efficiency across China tends to be low and can be spatially characterized by a transformation such that the inefficiencies noted in 2000 have subsequently been transformed to comprise a three-tiered structure that encompasses northern, central, and southern cores. Third, variation in absolute and relative marine environmental efficiency differences for the coastal regions of China have been consistent over time; values initially decreased before increasing again in a fluctuating manner over the time period of this analysis. Fourth, data show that the Pearl River Delta area has experienced the highest rate of change in marine environmental efficiency over time when economic zones are used as basic research units, although values have nevertheless fluctuated significantly. Fifth, values for total factor productivity as well as technical efficiency and change across the Chinese marine economy all fluctuated over time but increased. Data show that changes in marine environmental efficiency across China can primarily be attributed to progress in marine science and technology. Finally, levels of capital investment and marine industrial pollution intensity are not significantly correlated with marine environmental efficiency. Indeed, both marine industrial structural levels and environmental protection technologies have had a positive effect on environmental efficiency while levels of investment in marine scientific research as well as the scale of economic development, the marine economy, and the degree of external openness have all exerted negative effects on this key variable. 展开更多
关键词 marine environmental efficiency undesirable output SBM-Malmquist model Tobit regression analysis
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Determining the Technical Efficiency of Specialty Ophthalmology Hospital Using SFA and DEA: 2009-2011 被引量:2
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作者 Majid Heydari Azadeh Ahmadzadeh Ghasab +2 位作者 Haleh Mousavi Isfahani Mehdi Raadabadi Mohsen Barouni 《Health》 2014年第9期803-808,共6页
Introduction: During the last decade, the health sector of many countries in general has been faced significantly with the increase of health care costs and in particular with the growth in hospital costs, that a sign... Introduction: During the last decade, the health sector of many countries in general has been faced significantly with the increase of health care costs and in particular with the growth in hospital costs, that a significant part of it is due to the inefficient use of resources. The present study has been calculated the technical efficiency of the Specialty Ophthalmology Hospital of Tehran University of Medical Sciences by the comprehensive data analysis methods and stochastic frontier analysis. Methods: In this article, the technical efficiency of the Specialty Ophthalmology Hospital of Tehran University of Medical Sciences has been calculated by the years of 2009 to 2011, by the comprehensive data analysis methods and stochastic frontier analysis. For this purpose, the form of input-oriented data envelopment analysis approach was used by assuming the variable Productivity to scale and stochastic frontier analysis method and from the five output, the occupied bed days, outpatient admissions, inpatient admissions, inpatient days and bed occupancy factor, and from the six output, it means active beds, number of doctors, nurses, and other personnel, budget and equipment costs were used for the study. For data analyzing, Deap software, edit 1/2 and Frontier edit 1/4, was used. Result: The results of a comprehensive data analysis method showed: 1) The capacity of improving technical efficiency in the studied sector is 34% (average technical efficiency is 0.663 parts);and 2) some of the sectors are met the excess inputs (factors of production). Technical efficiency using stochastic frontier analysis was equal to 0.937. In fact, the stochastic frontier analysis showed the inefficiency is less than the actual value. Conclusion: Reducing excess capacity factors (factors of production) should be conducted in the form of a comprehensive plan and by considering all regarded aspects, that this reduction plays a major role in the hospital and health sector costs reduction. 展开更多
关键词 Technical efficiency Data Envelopment ANALYSIS Stochastic FRONTIER ANALYSIS Input output
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On the Efficiency for Non-Endoreversible Stirling and Ericsson Cycles 被引量:2
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作者 Delfino Ladino-Luna Pedro Portillo-Díaz Ricardo T. Páez-Hernández 《Journal of Modern Physics》 2013年第12期1-7,共7页
An analysis of the Stirling and Ericsson cycles from the point of view of the finite time thermodynamics is made by assuming the existence of internal irreversibilities in an engine modeled by these cycles, and the id... An analysis of the Stirling and Ericsson cycles from the point of view of the finite time thermodynamics is made by assuming the existence of internal irreversibilities in an engine modeled by these cycles, and the ideal gas as working substance is considered. Expressions of efficiency in both regimes maximum power output and maximum ecological function are also shown. Appropriate variables are introduced so that the objective functions, namely power output, ecological function and efficiency can be functions of the reservoirs temperatures ratio and certain “measurable” parameters as a thermal conductance, the general constant of gases and the compression ratio of the cycle. Several results from the finite time thermodynamics literature are used, so that the developed methodology leads directly to appropriate expressions of the objective functions in order to simplify the optimization process. 展开更多
关键词 Thermal Cycles efficiency Power output ECOLOGICAL Function
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Assessing Chinese Commercial Bank Technical Efficiency with a Parametric Hyperbolic Distance Function 被引量:1
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作者 Xuan Fang Feng Yang 《American Journal of Operations Research》 2014年第3期124-131,共8页
This paper contributes to the literatures about Chinese commercial banks technical efficiency. In order to eliminate the deviation of efficiency scores caused by an undesirable output that is represented by banks’ no... This paper contributes to the literatures about Chinese commercial banks technical efficiency. In order to eliminate the deviation of efficiency scores caused by an undesirable output that is represented by banks’ non-performing loans, the estimation is based on an enhanced parametric hyperbolic distance function which considers not only desirable outputs but also undesirable outputs. Furthermore, we extend the model to divide the factors that affecting technical efficiency into direct factors and indirect factors and exclude the influence of the latter when analyzing the determiners of banks technical efficiency. The validity of this model is examined by a panel of bank data from 2004-2010. 展开更多
关键词 PARAMETRIC DISTANCE FUNCTIONS Chinese BANK efficiency Undesirable outputs
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Energy efficiency and economic growth of China:1953-2006 被引量:1
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作者 Zhang Jian 《Ecological Economy》 2009年第2期122-131,共10页
Energy plays an important role in the economic life. With the rapid development of economy, the constraint of energy on the sustainable development of economy is becoming more and more obvious. This paper just Studies... Energy plays an important role in the economic life. With the rapid development of economy, the constraint of energy on the sustainable development of economy is becoming more and more obvious. This paper just Studies the factors influencing energy efficiency of China and the relationship between energy efficiency and China's economic: growth. By using time series multivariable linear regression methods with China's relevant data from 1953 to 2006, this paper constructs the regression model to analyze the factors that would impact energy, efficiency. After that, a regression model of China's real output to capital, labor and energy e lficiency is conducted to estimate the marginal contribution of every factor to the real output to prove the fundamental influence of energy efficiency to the economic growth. In the end, some policies and recommendations are also put forward in order to improve the energy efficiency; of China. 展开更多
关键词 Energy efficiency impact factor Economic growth Input and output
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Toward the Energy Efficiency of Resource Allocation Algorithms for OFDMA Downlink MIMO Systems
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作者 Wei-Chiang Wu 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第4期357-370,共14页
The problem of the simultaneous multi-user resource allocation algorithm in orthogonal frequency division multiple access(OFDMA)based systems has recently attracted significant interest.However,most studies focus on m... The problem of the simultaneous multi-user resource allocation algorithm in orthogonal frequency division multiple access(OFDMA)based systems has recently attracted significant interest.However,most studies focus on maximizing the system throughput and spectral efficiency.As the green radio is essential in 5G and future networks,the energy efficiency becomes the major concern.In this paper,we develop four resource allocation schemes in the downlink OFDMA network and the main focus is on analyzing the energy efficiency of these schemes.Specifically,we employ the advanced multi-antenna technology in a multiple input-multiple output(MIMO)system.The first scheme is based on transmit spatial diversity(TSD),in which the vector channel with the highest gain between the base station(BTS)and specific antenna at the remote terminal(RT)is chosen for transmission.The second scheme further employs spatial multiplexing on the MIMO system to enhance the throughput.The space-division multiple-access(SDMA)scheme assigns single subcarrier simultaneously to RTs with pairwise“nearly orthogonal”spatial signatures.In the fourth scheme,we propose to design the transmit beamformers based on the zero-forcing(ZF)criterion such that the multi-user interference(MUI)is completely removed.We analyze the tradeoff between the throughput and power consumption and compare the performance of these schemes in terms of the energy efficiency. 展开更多
关键词 Energy efficiency multiple input-multiple output(MIMO) multi-user resource allocation orthogonal frequency division multiple access(OFDMA) space-division multiple-access(SDMA) spatial multiplexing
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Study on the Regional Distribution of Energy Efficiency from the Point of Pollutant Emissions
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作者 Shen Neng 《Chinese Journal of Population,Resources and Environment》 2011年第3期58-65,共8页
In this paper, the author uses super-efficiency DEA model to measure the national and regional energy efficiency in China; using spatial econometric model and from the perspective of geo-spatial spillover, the author ... In this paper, the author uses super-efficiency DEA model to measure the national and regional energy efficiency in China; using spatial econometric model and from the perspective of geo-spatial spillover, the author interprets the spatial characteristies of energy efficiency and extracts the main factors that influ- ence the regional energy efficiency. The analysis results show that: (1) the national and regional energy efficiency is consistent with inverted U-shaped curve, and the nationwide energy efficiency gap is increasing; (2) energy efficiency has the obvious effect of the spatial external effect, and when the government makes energy saving strategies, inter-regional energy cooperation and the prolif- eration of advanced production technology should be given more priority; (3) energy efficiency has significant negative correlation with government intervention, industrial structure, ownership structure, the energy consumption structure, and resource endowments, and has positive correlation with the degree of opening-up and energy price. 展开更多
关键词 energy efficiency undesirable output space dependence
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Analysis on Evaluating Comprehensive Efficiency of Enterprise Leaders' Performance Based on Scientific Development Outlook
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作者 WANG Wei 《Chinese Business Review》 2007年第2期47-53,共7页
In former researches there are primary theoretical studies and qualitative analyses on enterprise leaders' effectiveness and performance, and there are a few studies on quantitative analyses which mostly relies on th... In former researches there are primary theoretical studies and qualitative analyses on enterprise leaders' effectiveness and performance, and there are a few studies on quantitative analyses which mostly relies on the method of comparing differences and ratio of divergence to evaluate leaders' performance by stage statistics. This paper illustrates how to evaluate Comprehensive Efficiency (CE) based on Scientific Development Outlook, which reflects overall development of enterprise leaders' performance, depends on measuring Output Efficiency Index (OEI) and Cost Efficiency Index (CEI) of enterprise leaders' performance, and adopts the C^2R model in Data Envelopment Analysis (DEA). 展开更多
关键词 enterprise leaders' performance Scientific Development Outlook Comprehensive efficiency output efficiency Index Cost efficiency Index
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Optimization of energy efficiency for the full-duplex massive MIMO systems 被引量:2
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作者 Xinhua Wang Ju Liu +2 位作者 Chao Zhai Pengbo Xing Lina Zheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期326-332,共7页
The energy efficiency(EE) for the full-duplex massive multi-input multi-output(MIMO) system is investigated. Given the transmit powers of both the uplink and the downlink, the closed-form solutions of the optimal ... The energy efficiency(EE) for the full-duplex massive multi-input multi-output(MIMO) system is investigated. Given the transmit powers of both the uplink and the downlink, the closed-form solutions of the optimal number of antennas and the maximum EE are achieved in the high regime of the signal-to-noise ratio(SNR). It is shown that the optimal number of antennas and the maximum EE gets larger with the increase in user numbers. To further improve the EE, an optimization algorithm with low complexity is proposed to jointly determine the number of antennas and the transmit powers of both the uplink and the downlink. It is shown that, the proposed algorithm can achieve the system performance very close to the exhaustive search. 展开更多
关键词 energy efficiency(EE) full-duplex fractional programming massive multi-input multi-output(MIMO)
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New High Efficiency LED Lighting Solution
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作者 DING Ke NIU Ping-juan FU Xian-song 《Semiconductor Photonics and Technology》 CAS 2008年第3期213-216,共4页
As the quality of power LED improves and the cost of power LED reduces, semiconductor lighting will replace incandescent and fluorescent lighting gradually, causing another revolution on the lighting history. And its ... As the quality of power LED improves and the cost of power LED reduces, semiconductor lighting will replace incandescent and fluorescent lighting gradually, causing another revolution on the lighting history. And its driving solution has been greatly accelerated. Based on the white power LED I-V characteristics and the application ambiance, proposed is a new LED lighting solution, suiting indoor and outdoor illumination. According to the test results, the design is optimized, and the electrical efficiency is 95% and the output current deviation is 13.0%. 展开更多
关键词 LED lighting electrical efficiency output current deviation
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A 1.8 GHz Power Amplifier Class-E with Good Average Power Added Efficiency
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作者 Mousa Yousefi Ziaadin Daie Koozehkanani +1 位作者 Jafar Sobhi Hamid Jangi 《Circuits and Systems》 2013年第8期504-509,共6页
This paper presents a 1.8 GHz class-E controlled power amplifier (PA). The proposed power amplifier is designed with two-stage architecture. The main advantage of the proposed technique for output control power is a h... This paper presents a 1.8 GHz class-E controlled power amplifier (PA). The proposed power amplifier is designed with two-stage architecture. The main advantage of the proposed technique for output control power is a high 37 dB output power dynamic range with good average power adding efficiency. The measurement results show that the PA achieves a high power gain of 23 dBm and power added efficiency (PAE) by 38%. The circuit was post layout simulated in a standard 0.18 μm CMOS technology. 展开更多
关键词 POWER Added efficiency POWER AMPLIFIER CLASS-E Dynamic Range POLAR Modulation output POWER
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考虑非期望产出的我国物流业效率空间关联网络结构分析 被引量:1
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作者 花均南 胡美佳 《铁道运输与经济》 北大核心 2024年第4期42-50,共9页
深入研究非期望产出的我国物流业效率的空间关联网络对于推进物流业的低碳转型,促进物流产业区域协同发展具有重要的现实意义。基于2011—2020年我国内陆30个省份的数据,利用超效率SBM模型测算考虑非期望产出的物流业效率,借助修正的引... 深入研究非期望产出的我国物流业效率的空间关联网络对于推进物流业的低碳转型,促进物流产业区域协同发展具有重要的现实意义。基于2011—2020年我国内陆30个省份的数据,利用超效率SBM模型测算考虑非期望产出的物流业效率,借助修正的引力模型和社会网络分析方法对效率空间关联网络特征及其影响因素进行了分析。结果表明:考虑非期望产出的物流业效率空间关联效应已经突破了地理邻近范围,其空间关联网络结构较为稳定但松散。研究期内,空间关联网络中各地区物流产业辐射关联能力及中介作用表现情况不同。地理位置、经济发展水平差异、科技水平差异和政府支持力度差异对考虑非期望产出的物流业效率空间关联网络结构的形成有显著影响。 展开更多
关键词 非期望产出 物流业效率 超效率SBM模型 空间网络结构 社会网络分析
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