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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 Hao Wanming 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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Joint Optimization of Satisfaction Index and Spectrum Efficiency with Cache Restricted for Resource Allocation in Multi-Beam Satellite Systems 被引量:4
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作者 Pei Zhang Xiaohui Wang +1 位作者 Zhiguo Ma Junde Song 《China Communications》 SCIE CSCD 2019年第2期189-201,共13页
Dynamic resource allocation(DRA) is a key technology to improve system performances in GEO multi-beam satellite systems. And, since the cache resource on the satellite is very valuable and limited, DRA problem under r... Dynamic resource allocation(DRA) is a key technology to improve system performances in GEO multi-beam satellite systems. And, since the cache resource on the satellite is very valuable and limited, DRA problem under restricted cache resources is also an important issue to be studied. This paper mainly investigates the DRA problem of carrier resources under certain cache constraints. What's more, with the aim to satisfy all users' traffic demands as more as possible, and to maximize the utilization of the bandwidth, we formulate a multi-objective optimization problem(MOP) where the satisfaction index and the spectrum efficiency are jointly optimized. A modified strategy SA-NSGAII which combines simulated annealing(SA) and non-dominated sorted genetic algorithm-II(NSGAII) is proposed to approximate the Pareto solution to this MOP problem. Simulation results show the effectiveness of the proposed algorithm in terms of satisfaction index, spectrum efficiency, occupied cache, and etc. 展开更多
关键词 GEO MULTI-BEAM satellite system dynamic resource allocation SA-NSGAII CACHE SATISFACTION index spectrum efficiency
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Spectral Efficiency and Power Allocation for Mixed-ADC Massive MIMO System 被引量:7
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作者 Mengjiao Zhang Weiqiang Tan +1 位作者 Junhui Gao Shi Jin 《China Communications》 SCIE CSCD 2018年第3期112-127,共16页
This paper investigates the achievable uplink spectral efficiency(SE) of a massive multi-input multi-output(MIMO) system with a mixed analog-to-digital converter(ADC) receiver architecture, in which some antennas are ... This paper investigates the achievable uplink spectral efficiency(SE) of a massive multi-input multi-output(MIMO) system with a mixed analog-to-digital converter(ADC) receiver architecture, in which some antennas are equipped with full-resolution ADCs while others are deployed with low-resolution ADCs. We derive the theoretical results and corresponding approximate expressions of the achievable SE in multi-cell systems with maximum ratio combining(MRC) detector and in single-cell systems with zero-forcing(ZF) detector. Based on approximated results, the effects of physical parameters, including the transmit power, the number of antennas, the proportion of full-resolution ADCs and the quantization precision of the low-resolution ADCs on the achievable SE are revealed. Furthermore, we propose the power allocation algorithms based on the lower bound and upper bound of approximate achievable SE. Our results show that the total achievable SE improves by increasing the number of BS antennas, the signal-to-noise ratio(SNR), and the quantization precision. Results showcase that proposed power allocation algorithms remarkably improve the total achievable SE comparing to the equal power allocation algorithm, which verifies the effectiveness of our proposed schemes. 展开更多
关键词 massive MIMO mixed-ADC ar-chitecture MRC detector ZF detector spec-tral efficiency power allocation scheme.
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An Empirical Study of the Allocation Efficiency of Rural Financial Resources in Hubei Province from the Perspective of Agricultural Loans 被引量:3
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作者 Xiaofang ZOU Xueqin JIANG 《Asian Agricultural Research》 2014年第8期38-41,共4页
The incompatibility of China's economy and finance has to some extent inhibited the development of rural economy. Taking Hubei Province for example,we measure the allocation efficiency of rural financial resources... The incompatibility of China's economy and finance has to some extent inhibited the development of rural economy. Taking Hubei Province for example,we measure the allocation efficiency of rural financial resources from the perspective of agricultural input and output,and use the modern rural financial development theory to set forth some policy recommendations on how to build a new rural financial resource allocation system. Studies have shown that the allocation efficiency of rural financial resources is low in China,and improving the allocation efficiency of rural financial resources is the key to perfecting rural financial environment while increasing financial support for agriculture. 展开更多
关键词 RURAL FINANCIAL RESOURCES allocation efficiency FI
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An Optimal Bit-Rate Allocation Algorithm to Improve Transmission Efficiency of Images in Deep Space Exploration 被引量:2
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作者 Yong Xu Jionghui Li +1 位作者 Xiangyu Lin Fan Bai 《China Communications》 SCIE CSCD 2020年第7期94-100,共7页
As fixed compression ratio is used in traditional deep space exploration image transmission application,the same compression code rate is allocated to each image.However,since the information of each image in a space ... As fixed compression ratio is used in traditional deep space exploration image transmission application,the same compression code rate is allocated to each image.However,since the information of each image in a space observation mission is nonuniform,the image with more information will inevitably lead to more compression distortion than the image with less information.Obviously,it’s not an efficient way to transmit information in terms of data importance or overall distortion.Therefore,we proposed a combinatorial optimal bit rate allocation algorithm to improve the efficiency of image transmission in space application.Different from traditional method,the rate-distortion model of wavelet coefficients for each image in a transmission task was built,and under the overall maximum transmission rate constraint,an bit-rate optimal allocation was applied for each image to minimize the overall distortion of a batch of images.The proposed algorithm can be widely used in image compression algorithm with embedded code stream characteristics,such as JPEG2000 and SPIHT.Experimental results shows that in the range of 2.6 to 10 compression ratio,the algorithm can reduce image distortion MSB by 40%~64%at the same overall transmission code rate,which equivalent to improvement of PSNR 3 dB to 5.4 dB. 展开更多
关键词 JPEG2000 efficiency DISTORTION
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A Robust Energy Efficiency Power AllocationAlgorithm in Cognitive Radio Networks 被引量:2
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作者 Mingyue Zhou Xiaohui Zhao 《China Communications》 SCIE CSCD 2018年第10期150-158,共9页
In order to solve the problem that traditional energy efficiency power allocation algorithms usually require the assumption of constant or perfect channel state information in cognitive radio networks(CRNs),which may ... In order to solve the problem that traditional energy efficiency power allocation algorithms usually require the assumption of constant or perfect channel state information in cognitive radio networks(CRNs),which may lead to performance degradation in real systems with disturbances or uncertainties,we propose a robust energy efficiency power allocation algorithm for underlay cognitive radio(CR)systems with channel uncertainty in consideration of interference power threshold constraint and minimum target SINR requirement constraint.The ellipsoid sets are used to describe the channel uncertainty,and a constrained fractional programming for the allocation is transformed to a convex optimization problem by worst-case optimization approach.A simplified version of robust energy efficiency scheme by a substitutional constraint having lower complexity is presented.Simulation results show that our proposed scheme can provide higher energy efficiency compared with capacity maximization algorithm and guarantee the signal to interference plus noise ratio(SINR)requirement of each cognitive user under channel uncertainty. 展开更多
关键词 cognitive radio power allocation spectrum sharing
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A New Multi-Resource Allocation Mechanism: A Tradeoff between Fairness and Efficiency in Cloud Computing 被引量:2
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作者 Lihua Zhao Minghui Du Lin Chen 《China Communications》 SCIE CSCD 2018年第3期57-77,共21页
This paper addresses multi-resource fair allocation: a fundamental research topic in cloud computing. To improve resource utilization under well-studied fairness constraints, we propose a new allocation mechanism call... This paper addresses multi-resource fair allocation: a fundamental research topic in cloud computing. To improve resource utilization under well-studied fairness constraints, we propose a new allocation mechanism called Dominant Resource with Bottlenecked Fairness(DRBF), which generalizes Bottleneck-aware Allocation(BAA) to the settings of Dominant Resource Fairness(DRF). We classify users into different queues by their dominant resources. The goals are to ensure that users in the same queue receive allocations in proportion to their fair shares while users in different queues receive allocations that maximize resource utilization subject to well-studied fairness properties such as those in DRF. Under DRBF, no user 1) is worse off sharing resources than dividing resources equally among all users; 2) prefers the allocation of another user; 3) can improve their own allocation without reducing other users' allocations; and(4) can benefit by misreporting their resource demands. Experiments demonstrate that the proposed allocation policy performs better in terms of high resource utilization than does DRF. 展开更多
关键词 multi-resource fairness allocation cloud computing resource utilization
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Energy efficiency based joint cell selection and power allocation scheme for HetNets 被引量:2
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作者 Kwabena Kobia Mensah Rong Chai +1 位作者 Denis Bilibashi Feifei Gao 《Digital Communications and Networks》 SCIE 2016年第4期184-190,共7页
Heterogeneous networks (HetNets) composed of overlapped cells with different sizes are expected to improve the transmission performance of data service significantly. User equipments (UEs) in the overlapped area o... Heterogeneous networks (HetNets) composed of overlapped cells with different sizes are expected to improve the transmission performance of data service significantly. User equipments (UEs) in the overlapped area of multiple cells might be able to access various base stations (BSs) of the cells, resulting in various transmission performances due to cell heterogeneity. Hence, designing optimal cell selection scheme is of particular importance for it may affect user quality of service (QoS) and network performance significantly. In this paper, we jointly consider cell selection and transmit power allocation problem in a HetNet consisting of multiple cells. For a single UE case, we formulate the energy efficiency of the UE, and propose an energy efficient optimization scheme which selects the optimal cell corresponding to the maximum energy efficiency of the UE. The problem is then extended to multiple UEs case. To achieve joint performance optimization of all the UEs, we formulate an optimization problem with the objective of maximizing the sum energy efficiency of UEs subject to QoS and power constraints. The formulated nonlinear fractional optimization problem is equivalently transformed into two subproblems, i.e., power allocation subproblem of each UE-eell pair, and cell selection subproblem of UEs. The two subproblems are solved respectively through applying Lagrange dual method and Kuhn-Munkres (K- M) algorithm. Numerical results demonstrate the efficiency of the proposed algorithm. 展开更多
关键词 Energy efficiency HetNets Cellular network Kuhn-Munkres LAGRANGE
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Biomass allocation and assimilation efficiency of natural Tilia amurensis samplings in response to different light regimes
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作者 徐程扬 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第2期69-74,共6页
Biomass allocation and assimilation efficiency of natural Amour linden (Tilia amurensis) samplings in different light regimes were analyzed in the paper. The results showed that shoot increment of samplings in gap was... Biomass allocation and assimilation efficiency of natural Amour linden (Tilia amurensis) samplings in different light regimes were analyzed in the paper. The results showed that shoot increment of samplings in gap was the highest and that of samplings under canopy was the least. Samplings in gap expressed apical dominance strongly but samplings in full sun and under canopy behaved intensive branching. Lateral competition or moderate shading was favored to bole construction. The patters of biomass allocation of samplings in different light environment were rather similar. The biomass translocated to stem was more than that to other organs, and about one half of photosynthate was used to support leaf turn over. On the contrary, photosynthates of samplings in full sun were mostly consumed in leaves bearing and energy balancing. The carbon assimilation for leaves of samplings in gap was the most efficient, and more carbons were fixed and translocated to non-photosynthetic organs, especially to stemwood. 展开更多
关键词 Tilia amurensis Shoot growth Biomass allocation Assimilation efficiency of leaf Light environment
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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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Optimal Energy Efficiency Resource Allocation Strategy for Cognitive Clustering Network under PUEA Attack
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作者 Linna Hu Ning Cao +3 位作者 Rui Shi Xue Cai Minghe Mao Zhiyu Chen 《China Communications》 SCIE CSCD 2020年第10期249-263,共15页
5G has pushed the use of radio spectrum to a new level,and cognitive clustering network can effectively improve the utilization of radio spectrum,which is a feasible way to solve the growing demand for wireless commun... 5G has pushed the use of radio spectrum to a new level,and cognitive clustering network can effectively improve the utilization of radio spectrum,which is a feasible way to solve the growing demand for wireless communications.However,cognitive clustering network is vulnerable to PUEA attack,which will lead to the degradation of system detection performance,thereby reducing the energy efficiency.Aiming at these problems,this paper investigates the optimal energy efficiency resource allocation scheme for cognitive clustering network under PUEA attack.A cooperative user selection algorithm based on selection factor is proposed to effectively resist PUEA user attack and improve detection performance.We construct the energy efficiency optimization problem under multi-constraint conditions and transform the nonlinear programming problem into parametric programming problem,which is solved by Lagrangian function and Karush-Kuhn-Tucker condition.Then the sub-gradient iterative algorithm based on optimal energy efficiency under PUEA attack is proposed and its complexity is analyzed.Simulation results indicate that proposed method is effective when subjected to PUEA attacks,and the impact of different parameters on energy efficiency is analyzed. 展开更多
关键词 cognitive clustering network energy efficiency resource allocation PUEA cooperative user selection
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Photosynthetic Carbon Gain, Allocation and Resources-Use Efficiency in Invasive Eupatorium Adenophorum and Its Native Congener E. Japonicum under Different Light and Nutrient Conditions
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作者 Jiye QIANG Ruifang WANG 《Agricultural Science & Technology》 CAS 2017年第10期1832-1840,共9页
Invasion is often facilitated by high resources availabilities and suppressed under low resources habitats. However, a number of invasive plants can successfully establish and dominate in resource-poor and (or) the ... Invasion is often facilitated by high resources availabilities and suppressed under low resources habitats. However, a number of invasive plants can successfully establish and dominate in resource-poor and (or) the understory of closed forests, indicating the plant's performances are habitats-dependent and species-specific. It is therefore necessary to explore the ecophysiological characteristics associated invasiveness for one invasive species across multiple resources availabilities whilst taking the relatedness into these comparative studies. In this study, invasive Eupitorium adenophorum and its native congener E. japonicum grew under different resource gradients in terms of light levels and soil nitrogen additions to identify the functional significance morphological and physiological traits associated closely with invasion and to examine their comparative responses. Photosynthetic carbon gain, biomass allocation and resource-use efficiency are evaluated in this pot experiment. Across treatments, E. adenophorum exhibited consistently higher values for most of the morphological variables including plant stature, relative growth rate (RGR), leaf root ratio (LRR), leaf area ratio (LAR), total leaf area, and lower root: shoot ratio (RSR). Significantly higher Pmax corresponded with higher photosynthetic nitrogen use efficiency (PNUE) and photosynthetic energy use efficiency (PEUE) especially in low light and (or) unfertile condition. Higher Gs and Pmax but lower photosynthetic water use efficiency (WUE) indicated the trade-off relationship between WUE and PNUE for E. adenophorum. Final biomasses were higher for E. adenophorum in nutrient and(or) light limited conditions, in which higher leaf construction cost(CC) compared with E. japonicum could be over-compensated by its significantly higher assimilation rates. The effects of light levels on these plant attributes were stronger than soil nutrient contents. The responses of these two congeneric species to light and nitrogen availabilities were similar, but the differences were magnified in resources limited conditions, indicating the better performancer at acquiring and at using limited resources of E. adenophorum over its co-occurring native flora. Our study presented the distinctive advantages of E. adenophorum in resources-poor environments, indicating conventional strategy of managing resources levels to control the invasion and expending of exotic species may not be as effective as expected. 展开更多
关键词 INVASIVENESS Biomass allocation Resource utilization efficiency Construction cost PHENOLOGY
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Literature Review on the Impact of Blockchain Technology on Resource Allocation Efficiency
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作者 Nuoya LIN Li'nan JIN +2 位作者 Jiaming LI Xiaofei LI Yihan XU 《Asian Agricultural Research》 2022年第6期18-20,共3页
With the rapid development of Internet technology,the importance of blockchain technology has become increasingly prominent.Faced with this situation,extensive research has been carried out at home and abroad.Through ... With the rapid development of Internet technology,the importance of blockchain technology has become increasingly prominent.Faced with this situation,extensive research has been carried out at home and abroad.Through the analysis of relevant literature on blockchain in recent years,it is found that there are many research results of blockchain technology in medical care,finance,education,etc.,but its application in the field of resource allocation efficiency is rare.From the existing studies on the influencing factors of resource allocation efficiency in China,it is found that there are significant differences in resource allocation efficiency between China and some developed countries or between various provinces and cities of China. 展开更多
关键词 Blockchain Resource allocation efficiency Influencing factors Literature review
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Application of Blockchain Technology in Optimizing Resource Allocation Efficiency
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作者 Jiaming LI Yihan XU +2 位作者 Li'nan JIN Nuoya LIN Xiaofei LI 《Asian Agricultural Research》 2022年第7期19-21,共3页
Based on the existing literature,this paper analyzed and explored the factors that affect the efficiency of resource allocation,and evaluated the current situation of resource allocation in various fields.It is found ... Based on the existing literature,this paper analyzed and explored the factors that affect the efficiency of resource allocation,and evaluated the current situation of resource allocation in various fields.It is found that with the emergence of the new pattern of China’s economic development,the economic growth rate has slowed down,and the method of large-scale production driving economic growth is no longer applicable to the current economic situation.Nowadays,when structural transformation and upgrading have entered a new stage,to achieve the optimization of resource allocation efficiency,it is necessary to start from three aspects:improving information transparency,upgrading industrial structure,and planning government intervention.Through the adaptation analysis of blockchain technology and the existing problems in optimizing resource allocation efficiency,it explored the feasibility of blockchain technology to optimize resource allocation efficiency,and promote economical,efficient and high-quality development. 展开更多
关键词 Resource allocation efficiency Blockchain technology High-quality economic development APPLICATION
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Inter-Basin Water Transfer Projects and Climate Change: The Role of Allocation Protocols in Economic Efficiency of the Project. Case Study: Dez to Qomrood Inter-Basin Water Transmission Project (Iran)
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作者 Reza Maknoon Masoud Kazem Maryam Hasanzadeh 《Journal of Water Resource and Protection》 2012年第9期750-758,共9页
Nowadays, there is a growing emphasis on Inter-basin water transfer projects as costly activities with ambiguous effects on environment, society and economy. Since the concept of climate change was in its embryonic ph... Nowadays, there is a growing emphasis on Inter-basin water transfer projects as costly activities with ambiguous effects on environment, society and economy. Since the concept of climate change was in its embryonic phase before 1990’s, the majority of these projects planned before that period have not considered the effect of long term variation of water resources. In all of these numerous operational and under-construction projects, an intelligent selection of the best water transmission protocol, can help the governments to optimize their expenditures on these projects ,and also can help water resources managers to face climate change effects wisely. In this paper as a case study, Dez to Qomrood inter-basin water transfer project is considered to evaluate the efficiency of three different protocols in long term. The effect of climate change has been forecasted via a wide range of GCMs (Global Circulation Model) in order to calculate the change of flow in the basin's area with different climate scenarios. After these calculation, a water allocation model has been used to evaluate which of these three water transmission protocols (Proportional Allocation (PA), Fix Upstream allocation (FU), and Fix Downstream allocation (FD)) is the most efficient logic switch economically in a framework including both upstream and downstream stakeholders. As the final result, it can be inferred that Fix Downstream allocation (FD) protocol can supply more population especially with urban water for a fix expense and also is the most adapted protocol with future global change, at least in the first round of sustainability assessment. 展开更多
关键词 WATER Transfer Economic efficiency CLIMATE Change WATER Transmission Protocols
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Research on Labor Reallocation Efficiency of State-owned Industries
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作者 Li Weitao 《Review of Global Academics》 2014年第2期178-180,共3页
This article,which is based on panel data of Chinese state-owned industrial enterprises over the period 2006-2011,analyzes Labor reallocation Efficiency of State-Owned Enterprises with Syrquin's analysis of the total... This article,which is based on panel data of Chinese state-owned industrial enterprises over the period 2006-2011,analyzes Labor reallocation Efficiency of State-Owned Enterprises with Syrquin's analysis of the total Reallocation effect of Resources. The results show that:①Labor allocation efficiency keeps a high level all the time;②The contribution that labor Reallocation efficiency makes to the growth of labor productivity has been at a low rate. Therefore, our government had better deepen the reform of state-owned enterprises and the evolvement of marketization 展开更多
关键词 State-owned Enterprises Labor allocation efficiency Capital allocationefficiency
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Super Efficiency and Misallocation: Evidence from Vietnamese Electric-Computer Industry
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作者 Nguyen Khac Minh Pham Van Khanh Nguyen Thi Phuong 《American Journal of Operations Research》 2018年第2期63-81,共19页
Misallocation means that the source is not distributed efficiently. This leads to an important question of how the relationship between misallocation and efficiency is (see [1]). The purpose of this study is to addres... Misallocation means that the source is not distributed efficiently. This leads to an important question of how the relationship between misallocation and efficiency is (see [1]). The purpose of this study is to address the empirical relationship between misallocation and efficiency in the electric and computer industry in Vietnam during the 2005-2015 periods. To do this, we built a model that allowed us to evaluate the impact of misallocation and other factors on efficiency. The slack-based measured efficiency (SBM) model (Tone [2]), and the super-efficient model (Tone [3]) are used to estimate the firms’ efficiency. The approach of Hsieh and Klenow [4] is used to measure misallocation in the study area. Estimated results of the model about the relationship between misallocation and efficiency show that the variable representing the misallocation has a negative sign and statistical significance in all models. In other words, the misallocation negatively affects efficiency. The bigger the misallocation, the lower the efficiency. 展开更多
关键词 Misallocation Super-efficient Slack-Based MEASURED efficiency
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Dual-radiation-chamber coordinated overall energy efficiency scheduling solution for ethylene cracking process regarding multi-parameter setting and multi-flow allocation
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作者 Di Meng Cheng Shao Li Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第6期180-197,共18页
Ethylene cracking process is the core production process in ethylene industry,and is paid more attention to reduce high energy consumption.Because of the interdependent relationships between multi-flow allocation and ... Ethylene cracking process is the core production process in ethylene industry,and is paid more attention to reduce high energy consumption.Because of the interdependent relationships between multi-flow allocation and multi-parameter setting in cracking process,it is difficult to find the overall energy efficiency scheduling for the purpose of saving energy.The traditional scheduling solutions with optimal economic benefit are not applicable for energy efficiency scheduling issue due to the neglecting of recycle and lost energy,as well as critical operation parameters as coil outlet pressure(COP)and dilution ratio.In addition,the scheduling solutions mostly regard each cracking furnace as an elementary unit,regardless of the coordinated operation of internal dual radiation chambers(DRC).Therefore,to improve energy utilization and production operation,a novel energy efficiency scheduling solution for ethylene cracking process is proposed in this paper.Specifically,steam heat recycle and exhaust heat loss are considered in cracking process based on 6 types of extreme learning machine(ELM)based cracking models incorporating DRC operation and three operation parameters as coil outlet temperature(COT),COP,and dilution ratio according to semi-mechanism analysis.Then to provide long-term decision-making basis for energy efficiency scheduling,overall energy efficiency indexes,including overall output per unit net energy input(OONE),output-input ratio per unit net energy input(ORNE),exhaust gas heat loss ratio(EGHL),are designed based on input-output analysis in terms of material and energy flows.Finally,a multiobjective evolutionary algorithm based on decomposition(MOEA/D)is employed to solve the formulated multi-objective mixed-integer nonlinear programming(MOMINLP)model.The validities of the proposed scheduling solution are illustrated through a case study.The scheduling results demonstrate that an optimal balance between multi-flow allocation,multi-parameter setting,and DRC coordinated operation is reached,which achieves 3.37%and 2.63%decreases in net energy input for same product output and conversion ratio,as well as the 1.56%decrease in energy loss ratio. 展开更多
关键词 Ethylene cracking process Energy efficiency scheduling Overall energy efficiency indexes Dual radiation chamber Multiple operation parameters Multiple energy flows
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An Optimal Model of the Total Amount Allocation for Surface Water Pollutants Based on the Principles of Equity and Efficiency
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作者 GAO Zi-ting PANG Tian-yi +4 位作者 ZHAO Wen-jin MA Duan-chao GAO Lei ZHANG Yu-nan LI Yu 《Meteorological and Environmental Research》 2012年第10期27-30,35,共5页
The control of total water pollutant amount is an effective method to improve quality of the groundwater, but how to allocate the total amount is an important and difficult work. In this paper, equity and efficiency w... The control of total water pollutant amount is an effective method to improve quality of the groundwater, but how to allocate the total amount is an important and difficult work. In this paper, equity and efficiency were bases of the total amount allocation. Took total amount allocation of the surface water pollutant in a car manufacturing group as an example, the current emissions and unit of output value as the bases for cluster analysis, the target unit was divided into "key reduction unit" and "concern reduction unit". Then, allocation scheme of the total amount was prepared. This model for research and improvement of the feasibility for total pollutant amount allocation technique has certain reference value. 展开更多
关键词 Total amount allocation Water contaminant Optimal model China
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A Literature Review of the Influence of Commercial Credit on the Efficiency of Enterprise Capital Allocation
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作者 Xinxiu Xie Tinghua Liu Fengjuan Kou 《Journal of Finance Research》 2021年第2期56-66,共11页
The real economy is the main body of high-quality development,and the efficiency of capital allocation is an important manifestation of the development of the real economy.Therefore,it is very important to study the e... The real economy is the main body of high-quality development,and the efficiency of capital allocation is an important manifestation of the development of the real economy.Therefore,it is very important to study the efficiency of capital allocation.As a representative of horizontal finance,commercial credit has a significant impact on the improvement of capital allocation efficiency.In view of this,this article combs the literature on commercial credit and capital allocation efficiency from the following aspects:firstly,by studying the literature,combing the literature on the macro-level,micro-level and economic effects of commercial credit;secondly,the measurement method of capital allocation efficiency And the influencing factors are systematically sorted out,and finally sorted out and evaluated the existing literature on the influence of commercial credit on the efficiency of capital allocation. 展开更多
关键词 Real economy Capital allocation efficiency Commercial credit
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