Estimating the Input Power of a Power Plant Using the Efficiency of the Inverter

The study focuses on estimating the input power of a power plant from available data, using the theoretical inverter efficiency as the key parameter. The paper addresses the problem of missing data in power generation systems and proposes an approach based on the efficiency formula widely documented in the literature. In the absence of input data, this method makes it possible to estimate the plant’s input power using data extracted from the site, in particular that provided by the Ministry of the Environment. The importance of this study lies in the need to accurately determine the input power in order to assess the overall performance of the energy system.

Secure Computation Efficiency Resource Allocation for Massive MIMO-Enabled Mobile Edge Computing Networks

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.

A Study on Input-Output Efficiency of Citrus in Jiangxi Province

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.

Meta-analysis of CO_(2) conversion,energy efficiency,and other performance data of plasma-catalysis reactors with the open access PIONEER database

This paper brings the comparison of performances of CO_(2)conversion by plasma and plasma-assisted catalysis based on the data collected from literature in this field,organised in an open access online database.This tool is open to all users to carry out their own analyses,but also to contributors who wish to add their data to the database in order to improve the relevance of the comparisons made,and ultimately to improve the efficiency of CO_(2)conversion by plasma-catalysis.The creation of this database and database user interface is motivated by the fact that plasma-catalysis is a fast-growing field for all CO_(2)conversion processes,be it methanation,dry reforming of methane,methanolisation,or others.As a result of this rapid increase,there is a need for a set of standard procedures to rigorously compare performances of different systems.However,this is currently not possible because the fundamental mechanisms of plasma-catalysis are still too poorly understood to define these standard procedures.Fortunately however,the accumulated data within the CO_(2)plasma-catalysis community has become large enough to warrant so-called“big data”studies more familiar in the fields of medicine and the social sciences.To enable comparisons between multiple data sets and make future research more effective,this work proposes the first database on CO_(2)conversion performances by plasma-catalysis open to the whole community.This database has been initiated in the framework of a H_(2)0_(2)0 European project and is called the“PIONEER Data Base”.The database gathers a large amount of CO_(2)conversion performance data such as conversion rate,energy efficiency,and selectivity for numerous plasma sources coupled with or without a catalyst.Each data set is associated with metadata describing the gas mixture,the plasma source,the nature of the catalyst,and the form of coupling with the plasma.Beyond the database itself,a data extraction tool with direct visualisation features or advanced filtering functionalities has been developed and is available online to the public.The simple and fast visualisation of the state of the art puts new results into context,identifies literal gaps in data,and consequently points towards promising research routes.More advanced data extraction illustrates the impact that the database can have in the understanding of plasma-catalyst coupling.Lessons learned from the review of a large amount of literature during the setup of the database lead to best practice advice to increase comparability between future CO_(2)plasma-catalytic studies.Finally,the community is strongly encouraged to contribute to the database not only to increase the visibility of their data but also the relevance of the comparisons allowed by this tool.

Layering Precision Land Leveling and Furrow Irrigated Raised Bed Planting: Productivity and Input Use Efficiency of Irrigated Bread Wheat in Indo-Gangetic Plains

Stagnating yield and declining input use efficiency in irrigated wheat of the Indo-Gangetic Plain (IGP) coupled with diminishing availability of water for agriculture is a major concern of food security in South Asia. The objective of our study was to establish an understanding of how wheat yield and input use efficiency can be improved and how land leveling and crop establishment practices can be modified to be more efficient in water use through layering of precision-conservation crop management techniques. The “precision land leveling with raised bed” planting can be used to improve crop yield, water and nutrient use efficiency over the existing “traditional land leveling with flat” planting practices. We conducted a field experiment during 2002-2004 at Modipuram, India to quantify the benefits of alternate land leveling (precision land leveling) and crop establishment (furrow irrigated raised bed planting) techniques alone or in combination (layering precision-conservation) in terms of crop yield, water savings, and nutrient use efficiency of wheat production in IGP. The wheat yield was about 16.6% higher with nearly 50% less irrigation water with layering precision land leveling and raised bed planting compared to traditional practices (traditional land leveling with flat planting). The agronomic (AE) and uptake efficiency (UE) of N, P and K were significantly improved under precision land leveling with raised bed planting technique compared to other practices.

Efficiency assessment of coal mine safety input by data envelopment analysis

In recent years improper allocation of safety input has prevailed in coal mines in China, which resulted in the frequent accidents in coal mining operation. A comprehensive assessment of the input efficiency of coal mine safety should lead to improved efficiency in the use of funds and management resources. This helps government and enterprise managers better understand how safety inputs are used and to optimize allocation of resources. Study on coal mine＇s efficiency assessment of safety input was con- ducted in this paper. A C^2R model with non-Archimedean infinitesimal vector based on output is established after consideration of the input characteristics and the model properties. An assessment of an operating mine was done using a specific set of input and output criteria. It is found that the safety input was efficient in 2002 and 2005 and was weakly efficient in 2003. However, the efficiency was relatively low in both 2001 and 2004. The safety input resources can be optimized and adjusted by means of projection theory. Such analysis shows that, on average in 2001 and 2004, 45% of the expended funds could have been saved. Likewise, 10% of the safety management and technical staff could have been eliminated and working hours devoted to safety could have been reduced by 12%. These conditions could have Riven the same results.

Input and output efficiency of urban agglomerations in China using DEA multi-stage model

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.

An application of data envelopment analysis to investigate the efficiency of lumber industry in northwestern Ontario,Canada

This study aims at exploring the technical efficiency of lum- ber industry in northwestern Ontario, Canada using data envelopment analysis （DEA）. The DEA model analyzes relative technical efficiency of lumber mills with disproportionate inputs and outputs by dividing the 10- year time series data, for inputs and outputs of 24 lumber mills, over two periods （1999-2003 and 2004-2008）. Four inputs, namely, material （log volume）, labour （man-hours）, two types of energy （hog-fuel and electric- ity）, and one output （lumber volume） are used in this study. The trend analysis shows an annual reduction of 10%, 13% and 13% for lumber output, log consumption （input） and number of employees, respectively, during the period 1999-2008. The results from DEA with two scenarios with energy inputs and without energy inputs, for the two periods are found to be mixed and interesting. While some mills have improved their performance in terms of best use of available scarce inputs in the second period, some have shown negative per cent change in efficiency. In the with energy input and the without energy input scenario, some of the mills show a reduction in efficiency in the second period from the first period, with the highest estimated reductions of-13.9% and -47.6%, respectively. A possible explanation for these negative performances of mills in the latter period is the decline in production in the second period compared to the first period, where these mills were not able to adjust their inputs （mostly labour） as proportional lay-offs might not have been possible. These results provide policy makers and industry stakeholders with an improved understanding of the trends of efficiency and employ- ment as well as reallocation opportunities of future inputs in order to increase benefits from this sector.

Determining the Technical Efficiency of Specialty Ophthalmology Hospital Using SFA and DEA: 2009-2011

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.

Research on a High-Efficiency LED Driving Circuit Based on Buck Topology

A high efficiency LED(Light Emitting Diode) driver based on Buck converter, which could operate under a wide AC input voltage range(85V^265V) and drive a series of high power LEDs, is presented in this paper. The operation principles, power loss factors of the LED driver in this study are analyzed and discussed in detail and some effective ways to improve efficiency are proposed through system design considerations. To verify the feasibility, a laboratory prototype is also designed and tested for an LED lamp which consists of 16 LUMILEDS LEDs in series. Experimental results show that a high efficiency of 92% at I0=350mA can be achieved and the studied driver might be practical for driving high power LEDs. In the last, the overall efficiency over 90% is gained through some experiments under variable input and output voltages and verifies the validity of the designed driver.

Energy efficiency and economic growth of China:1953-2006

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.

Optimization of energy efficiency for the full-duplex massive MIMO systems

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.

Assessing China’s regional efficiency of energy-saving and emission reduction using the target orientation approach of extended DDF model

Based on the target of energy-saving and emission reduction(ESER)in the national five-year plan in China,an extended directional distance function model(E-DDF)including undesirable input and undesirable output is proposed,and energy-saving efficiency,emission reduction efficiency,ESER efficiency are defined.Then the weighted directional distance function model is constructed for the total factors efficiency index model of ESER to reflect its dynamic change.The results show that the ESER efficiency continues to rise during the three five-year plan periods(2006-2017),and the efficiency score of the east area are higher than those of central and west area.The disparity and change of energy-saving efficiency among difference regions are not obvious,but the disparity and change of emission reduction efficiency are the main reasons for the improvement and change of ESER efficiency index.In the long run,the ESER efficiency is in a dynamic upward trend,and the effect of technological progress is more obvious compared with technical efficient index.

Toward the Energy Efficiency of Resource Allocation Algorithms for OFDMA Downlink MIMO Systems

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.

中国高技术产业科技成果转化效率和投入产出结构分析

为进一步探究我国高技术产业中各个行业科技成果转化效率及其投入产出结构,利用2009—2021年的面板数据,采用超效率SBM模型对中国高技术产业科技成果转化效率进行研究,分析中国高技术产业15个行业的科技成果转化综合效率和投入冗余、产出不足,为高技术产业及其行业调整优化投入产出结构、提升科技成果转化效率提供基础。研究发现,中国高技术产业科技成果转化效率呈现出先下降再波动上升的趋势,各行业均呈现波动上升的良好发展趋势,但整体水平不高,行业间差距较大;行业间R&D活动人员、技术改造经费和科技活动经费中的政府资金投入冗余,新产品销售收入产出不足问题突出。基于上述结论提出根据行业特点,先转换再精减冗余人员、重视科研人员再教育、调整资金分配结构、转变政府干预方式、建立健全多渠道合作机制、注重市场需求导向促进理论成果市场化等建议,以进一步提升高技术产业科技成果转化效率。

技术融合与企业出口产品质量--来自中国工业企业的经验证据

技术融合是提高科技成果转化和产业化水平、实现经济高质量发展取得新突破的关键。推动中国迈向贸易强国的背景下,研究技术融合究竟如何影响中国企业出口产品质量的问题尤为重要。使用2000—2013年中国工业企业数据作为研究样本,构建固定效应模型,系统考察技术融合对企业出口产品质量的影响及作用机制。研究发现,技术融合的深化显著提升了企业出口产品质量。异质性分析表明,技术融合对企业出口产品质量的提升作用在非国有企业、非外资企业以及沿海企业中表现更为突出。机制检验发现,技术融合深化能够提升企业全要素生产率以及固定成本投入效率,最终实现企业出口产品质量升级;市场化程度以及政府支持力度会在技术融合提升企业出口产品质量过程中发挥正向调节作用。因此,应进一步深化技术融合,搭建高效的交流合作平台,加速优质要素资源流动,重点培育本土企业自主创新能力,实现出口产品质量升级。

区域协同创新视角下广东省众创空间运行效率评价研究

众创空间的有效运行在很大程度上影响着区域创新效率。建立能够有效分析众创空间运行效率的科学评价体系,才能找到众创空间无序发展的问题所在,以实现其发展的辐射带动作用和价值利益的最大化。鉴于此,基于广东省众创空间2016—2020年有关面板数据,采用BCC模型和数据包络分析(DEA)-Malmquist指数模型相结合的方法,通过动静态结合对广东省众创空间运行效率进行客观评价分析,以期为提升众创空间服务的有效供给提供参考。结果表明:2018年是广东省众创空间转型发展的关键年份,逐渐从开始的规模化增长转型迈向高质量发展,但不同城市之间的综合效率水平极不平衡,综合效率最高的为1.000,最低的为0.384;广东省众创空间运行效率整体表现较好,处于逐年增长的态势,其中众创空间的整体运营管理水平和技术投入效率逐年提高,但单一的规模驱动增长模式很难保持持续增长,技术进步变化对众创空间运行效率的影响更加显著。因此,需要构建科学合理的众创空间运行评价指标体系,明晰正确的发展方向,减少资源冗余和浪费。

服务要素投入、行业生产率与中国制造业国际循环——基于出口视角

基于2000—2014年中国18个制造业行业向41个国家的出口数据,构建一个包含服务要素投入、企业学习效率和行业进入门槛的理论模型,从行业视角检验服务要素投入对制造业出口的影响及其作用机制。研究发现:服务要素投入显著促进了中国制造业的出口增长,对中间品的促进作用显著强于最终品,且这一效应主要由供给侧的制造业服务化推动,需求侧的影响不明显。机制检验结果表明:引入服务要素投入能够显著提升行业生产率,从而扩大出口规模,并且服务要素投入能与制造业生产率形成互补效应,进一步促进出口增长。异质性检验结果表明:与服务化水平较低的出口目的国相比,当目的国服务化水平较高时,服务化对出口扩张的促进效果更加显著;从服务业行业异质性的角度看,金融保险服务、专业研发服务和运输仓储服务等服务行业的投入显著提升了制造业生产率,进一步扩大了出口规模,对制造业“走出去”起到积极作用。

基于模糊DEMATEL-超效率DEA的可再生能源发电技术综合效益评估方法

“双碳”目标下,各类可再生能源发电技术发展迅速,综合权衡不同可再生能源发电方案的综合效益对可再生能源的优化设计具有重要意义。综合考虑经济效益、环境效益、能源效益和社会效益4个层面,提出了一种基于模糊决策试验和评价实验(decision making trial and evaluation laboratory,DEMATEL)与超效率数据包络分析(data envelopment analysis,DEA)模型的可再生能源发电技术综合效益评估方法。该方法分为投入-产出指标体系构建和综合评估2个阶段。首先,利用三角直觉模糊数处理模糊评价信息,将其与DEMATEL相结合量化各指标之间相互影响关系,基于指标间逻辑分析结果建立投入-产出评估指标体系。然后,基于超效率DEA模型对各可再生能源发电方案进行评估排序,结合投入冗余和产出不足分析结果给出各方案的针对性改善建议,以期为进一步选择和确定可再生能源产业发展战略提供参考。最后以某省10类可再生能源发电单元为研究对象,基于所提研究方法进行综合评估和分析,并与多准则妥协解排序法和熵权法进行对比分析,验证了所提方法的有效性。

基于DEA模型的安康市农业投入产出效率评价

为了解安康市现代农业发展效率状况,选取2009—2020年安康市污染治理投资总额、农业固定资产投资额、耕地面积和乡村劳动力资源总数4个农业投入指标,以及农业总产值和农业人均生产值2个农业产出指标,采用数据包络分析(data envelopment analysis,DEA)模型中的BCC模型进行效率分析。结果表明,安康市农业投入产出效率只有2020年的DEA模型是有效的,但从2009年开始,综合效率总体呈现上升趋势;从投入冗余率与产出不足率可以看出,安康市农业总产值基本不存在产出不足的现象,除2020年外,其余各年份在污染治理投资总额、农业固定资产投资额、耕地面积和乡村劳动力资源总数的投入在不同程度都存在冗余,投入结构不合理造成DEA模型无效。