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The effect of different agricultural management practices on irrigation efficiency, water use efficiency

La ZHUO, Arjen Y. HOEKSTRA

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 185-194 doi: 10.15302/J-FASE-2017149

摘要： This paper explores the effect of varying agricultural management practices on different water efficiency indicators: irrigation efficiency (IE), crop water use efficiency (WUE), and green and blue water footprint (WF). We take winter wheat in an experimental field in Northern China as a case study and consider a dry, average and wet year. We conducted 24 modeling experiments with the AquaCrop model, for all possible combinations of four irrigation techniques, two irrigation strategies and three mulching methods. Results show that deficit irrigation most effectively improved blue water use, by increasing IE (by 5%) and reducing blue WF (by 38%), however with an average 9% yield reduction. Organic or synthetic mulching practices improved WUE (by 4% and 10%, respectively) and reduced blue WF (by 8% and 17%, respectively), with the same yield level. Drip and subsurface drip irrigation improved IE and WUE, but drip irrigation had a relatively large blue WF. Improvements in one water efficiency indicator may cause a decline in another. In particular, WUE can be improved by more irrigation at the cost of the blue WF. Furthermore, increasing IE, for instance by installing drip irrigation, does not necessarily reduce the blue WF.

关键词： field management     irrigation efficiency     water footprint     water productivity     water use efficiency    

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Evaluating R&D efficiency of China’s listed lithium battery enterprises

《工程管理前沿（英文）》   页码 473-485 doi: 10.1007/s42524-022-0213-5

摘要： Promoting the growth of the lithium battery sector has been a critical aspect of China’s energy policy in terms of achieving carbon neutrality. However, despite significant support on research and development (R&D) investments that have resulted in increasing size, the sector seems to be falling behind in technological areas. To guide future policies and understand proper ways of promoting R&D efficiency, we looked into the lithium battery industry of China. Specifically, data envelopment analysis (DEA) was used as the primary approach based on evidence from 22 listed lithium battery enterprises. The performance of the five leading players was compared with that of the industry as a whole. Results revealed little indication of a meaningful improvement in R&D efficiency throughout our sample from 2010 to 2019. However, during this period, a significant increase in R&D expenditure was witnessed. This finding was supported, as the results showed that the average technical efficiency of the 22 enterprises was 0.442, whereas the average pure technical efficiency was at 0.503, thus suggesting that they were suffering from decreasing returns to scale (DRS). In contrast, the performance of the five leading players seemed superior because their average efficiency scores were higher than the industry’s average. Moreover, they were experiencing increasing scale efficiency (IRS). We draw on these findings to suggest to policymakers that supporting technologically intensive sectors should be more than simply increasing investment scale; rather, it should also encompass assisting businesses in developing efficient managerial processes for R&D.

关键词： Data Envelopment Analysis     R&D investment efficiency     China’s listed lithium battery enterprises     technical efficiency     pure technical efficiency     scale efficiency    

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Improving the efficiency and effectiveness of global phosphorus use: focus on root and rhizosphere levels

null

《农业科学与工程前沿（英文）》 2019年 第6卷 第4期   页码 357-365 doi: 10.15302/J-FASE-2019275

摘要：

Phosphorus (P) is essential for life and for efficient crop production, but global P use with limited recycling is inefficient in several sectors, including agronomy. Unfortunately, plant physiologists, agronomists, farmers and end users employ different measures for P use efficiency (PUE), which often masks their values at different scales. The term P use effectiveness, which also considers energetic and sustainability measures in addition to P balances, is also a valuable concept. Major physiological and genetic factors for plant P uptake and utilization have been identified, but there has been limited success in genetically improving PUE of modern crop cultivars. In maize, studies on root architectural and morphological traits appear promising. Rhizosphere processes assist in mobilizing and capturing sparingly soluble phosphate from rock phosphate. Combinations of phosphate-solubilizing microorganisms with ammonium-based nitrogen fertilizer, as well as strategies of fertilizer placement near the roots of target crops, can moderately enhance PUE. The desired concentration of P in the products differs, depending on the final use of the crop products as feed, food or for energy conversion, which should be considered during crop production.

关键词： acquisition efficiency     plant growth promoting rhizobacteria     phosphate     use efficiency     utilization efficiency    

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Optimization of power and efficiency for an irreversible Diesel heat engine

Shiyan ZHENG, Guoxing LIN

《能源前沿（英文）》 2010年 第4卷 第4期   页码 560-565 doi: 10.1007/s11708-010-0018-9

摘要： A cyclic model of an irreversible Diesel heat engine is presented, in which the heat loss between the working fluid and the ambient during combustion, the irreversibility inside the cyclic working fluid resulting from friction, eddies flow, and other irreversible effects are taken into account. By using the thermodynamic analysis and optimal control theory methods, the analytical expressions of power output and efficiency of the Diesel heat engine are derived. Variations of the main performance parameters with the pressure ratio of the cycle are analyzed and calculated. The optimum operating region of the heat engine is determined. Moreover, the optimum criterion of some important parameters, such as the power output, efficiency, pressure ratio, and temperatures of the working fluid at the related state points are illustrated and discussed. The conclusions obtained in the present paper may provide some theoretical guidance for the optimal parameter design of a class of internal-combustion engines.

关键词： Diesel heat engine     irreversibility     power output     efficiency     parameter optimization    

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Methods and applications of DEA cross-efficiency: Review and future perspectives

Jie WU, Jiasen SUN, Liang LIANG

《工程管理前沿（英文）》 2021年 第8卷 第2期   页码 199-211 doi: 10.1007/s42524-020-0133-1

摘要： The field of engineering management usually involves evaluation issues, such as program selection, team performance evaluation, technology selection, and supplier evaluation. The traditional self-evaluation data envelopment analysis (DEA) method usually exaggerates the effects of several inputs or outputs of the evaluated decision-making unit (DMU), resulting in unrealistic results. To address this problem, scholars have proposed the cross-efficiency evaluation (CREE) method. Compared with the DEA method, CREE can rank DMUs more completely by using reasonable weights. With the extensive application of this technique, several problems, such as non-unique weights and non-Pareto optimal results, have arisen in CREE methods. Therefore, the improvement of CREE has attracted the attention of many scholars. This paper reviews the theory and applications of CREE, including the non-uniqueness problem, the aggregation of cross-efficiency data, and applications in engineering management. It also discusses the directions for future research on CREE.

关键词： cross-efficiency evaluation     efficiency     secondary goal model     aggregation     review    

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STRATEGIES FOR IMPROVING WATER USE EFFICIENCY IN DRYLAND AGROECOSYSTEMS

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 599-602 doi: 10.15302/J-FASE -2021409

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Effects of dwarfing genes on water use efficiency of bread wheat

Jiakun YAN, Suiqi ZHANG

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 126-134 doi: 10.15302/J-FASE-2017134

摘要： Climate change has increased the risk of drought, which significantly limits plant productivity. Various ways of increasing water availability and sustaining growth of crop plants in drought-prone environments are available. Genetic advances in grain yields under rainfed conditions have been achieved with the introduction of dwarfing genes. A thorough understanding of the effects of different dwarfing genes on root growth, coleoptile length, grain yields and water using efficiency (WUE) will provide opportunities to select appropriate genes for breeding high WUE and grain yield cultivars. This review focuses on the mechanism involved in genes that reduce plant height and affect root and coleoptile length, their consequent effects on grain yields and WUE, and suggests that for rainfed and irrigation-limited environments, combining GAR and GAI dwarfing genes in breeding may help boost WUE and yields, and more materials from different parental sources should be collected to assess opportunities for potential comprehensive application of specific genes.

关键词： coleoptile length     wheat     dwarfing genes     grain yield     root     water use efficiency    

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neutrality potential of wastewater treatment plants: A novel evaluation framework integrating energy efficiency

《环境科学与工程前沿（英文）》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1549-0

摘要：

• Framework of indicators was established based on energy efficiency and recovery.

关键词： Wastewater treatment plants     Energy neutrality potential     Energy efficiency     Energy recovery     Evaluation framework    

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Approaches to achieve high grain yield and high resource use efficiency in rice

Jianchang YANG

《农业科学与工程前沿（英文）》 2015年 第2卷 第2期   页码 115-123 doi: 10.15302/J-FASE-2015055

摘要： This article discusses approaches to simultaneously increase grain yield and resource use efficiency in rice. Breeding nitrogen efficient cultivars without sacrificing rice yield potential, improving grain fill in later-flowering inferior spikelets and enhancing harvest index are three important approaches to achieving the dual goal of high grain yield and high resource use efficiency. Deeper root distribution and higher leaf photosynthetic N use efficiency at lower N rates could be used as selection criteria to develop N-efficient cultivars. Enhancing sink activity through increasing sugar-spikelet ratio at the heading time and enhancing the conversion efficiency from sucrose to starch though increasing the ratio of abscisic acid to ethylene in grains during grain fill could effectively improve grain fill in inferior spikelets. Several practices, such as post-anthesis controlled soil drying, an alternate wetting and moderate soil drying regime during the whole growing season, and non-flooded straw mulching cultivation, could substantially increase grain yield and water use efficiency, mainly via enhanced remobilization of stored carbon from vegetative tissues to grains and improved harvest index. Further research is needed to understand synergistic interaction between water and N on crop and soil and the mechanism underlying high resource use efficiency in high-yielding rice.

关键词： rice     nitrogen-efficient cultivar     grain fill     harvest index     nitrogen use efficiency     water use efficiency    

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A Comprehensive Evaluation of Policy Effectiveness for Energy Efficiency in Existing Buildings

Xing Wei,Han-ding Guo

《工程管理前沿（英文）》 2014年 第1卷 第4期   页码 341-347 doi: 10.15302/J-FEM-2014060

摘要： The healthy and stable development of energy efficiencies in existing buildings cannot be separated from effective policy operation, and evaluating policy effectiveness contributes to scientifically-sound government decision-making. This paper creates an evaluation index system and a grey comprehensive evaluation model for policy effectiveness for energy efficiency in existing buildings using three dimensions: 1) the effect of the policy itself; 2) the administrative effect of the policy; and 3) policy implementation effects. It chooses the government’s subsidy policy and preferential tax policy at market cultivation stage for its empirical comparative evaluation. The evaluation indicates that the former is more effective. Finally, it puts forward policy development suggestions from the perspective of: 1) clarifying incentive object; 2) broadening incentive scope; 3) increasing incentive intensity; and 4) innovating incentive mode.

关键词： grey comprehensive evaluation     existing buildings     energy efficiency     policies effectiveness    

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Regional characteristics of industrial energy efficiency in China: application of stochastic frontier

Tao HUANG,Akio ONISHI,Feng SHI,Masafumi MORISUGI,Mjo Lwin CHERRY

《环境科学与工程前沿（英文）》 2015年 第9卷 第3期   页码 506-521 doi: 10.1007/s11783-014-0656-y

摘要： This paper analyzed regional industrial energy efficiency in China with Total-Factor Energy Efficiency (TFEE). The East region has the best energy efficiency and the Central and the West regions stand as the second and the third respectively. However, it is found that industrial energy efficiency of all regions increased from 1998 to 2006. This result is consistent with level of economic development of every region. The industries of all provinces in China are not yet at the frontier efficiency position, therefore, to the frontier as target, their technology levels and production processes should be adjusted accordingly. Compared with the conventional energy efficiency, the inverse of energy intensity, which is defined as the ratio of actual output to energy input, is regarded as Single-Factor Energy Efficiency (SFEE) index. Although TFEE ranks are not changed for each region, they are different for each province. The comparative result also shows that the substitution among inputs (labor, capital stock, and energy) to produce the output is significant. The SFEE scores could be over-estimated if energy is taken as the single input in the production. Finally, we identified determining factors affecting industrial energy efficiency using Tobit model. The results indicate that an increase of per capita Gross Domestic Product (GDP), the percentage of output value of industry invested by Hong Kong, Macao, Taiwan and abroad, energy price and investment of scientific and technological activities for industry could be possible contributors and drivers to the industrial energy efficiency. However, increasing of heavy industry will lead to worse industrial energy efficiency.

关键词： industrial energy efficiency     stochastic frontier analysis     total-factor energy efficiency     single factor energy efficiency    

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Genetic study and molecular breeding for high phosphorus use efficiency in maize

null

《农业科学与工程前沿（英文）》 2019年 第6卷 第4期   页码 366-379 doi: 10.15302/J-FASE-2019278

摘要：

Phosphorus is the second most important macronutrient after nitrogen and it has many vital functions in the life of plants. Most soils have a low available P content, which has become a key limiting factor for increasing crop production. Also, low P use efficiency (PUE) of crops in conjunction with excessive application of P fertilizers has resulted in serious environmental problems. Thus, dissecting the genetic architecture of crop PUE, mining related quantitative trait loci (QTL) and using molecular breeding methods to improve high PUE germplasm are of great significance and serve as an efficient approach for the development of sustainable agriculture. In this review, molecular and phenotypic characteristics of maize inbred lines with high PUE, related QTL and genes as well as low-P responses are summarized. Based on this, a breeding strategy applying genomic selection as the core, and integrating the existing genetic information and molecular breeding techniques is proposed for breeding high PUE maize inbred lines and hybrids.

关键词： maize     phosphorus use efficiency     quantitative trait loci     genetic study     molecular breeding     genomic selection    

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Energy efficiency and carbon dioxide emissions reduction opportunities in district heating source in

Gaofeng CHEN, Xuejing ZHENG, Lin CONG

《能源前沿（英文）》 2012年 第6卷 第3期   页码 285-295 doi: 10.1007/s11708-012-0197-7

摘要： Building a trading market can promote energy conservation provided that the trading method is determined. Energy consumption for heat supply is huge. Tianjin Municipal Government is planning to establish an energy efficiency trading platform for district heating taking into consideration the experience in carbon trading market and specific situation in Tianjin. This paper presented an in-depth analysis of the district heating industry in Tianjin municipality, and identified the potentials of energy saving and carbon dioxide emissions reduction. Since energy efficiency was closely related to different heating source technologies, baselines were determined for boiler plants and thermal power plants respectively. Three scenarios were discussed for baseline determination. 472 boiler plants were surveyed and operational data relating to energy consumption were collected. Through data analysis, 27 boiler plants which have reasonable recorded energy consumption values were chosen as samples. By analyzing the dataset and referring to the related standards, method of determining the baseline for district heating carbon market was established. Finxally, the baseline for boiler plant was determined to be 52.0 kgce/GJ, and that for thermal power plant was 43.0 kgce/GJ in 2011. Carbon abatement against the baselines above was calculated and considerable carbon dioxide emissions reduction could be achieved.

关键词： district heating     energy efficiency     baseline     carbon abatement    

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Phosphorus use efficiency and fertilizers: future opportunities for improvements

null

《农业科学与工程前沿（英文）》 2019年 第6卷 第4期   页码 332-340 doi: 10.15302/J-FASE-2019274

摘要：

The continued supply of phosphate fertilizers that underpin global food production is an imminent crisis. The rock phosphate deposits on which the world depends are not only finite, but some are contaminated, and many are located in geopolitically unstable areas, meaning that fundamental changes will have to take place in order to maintain food production for a growing global population. No single solution exists, but a combination of approaches to phosphorus management is required not only to extend the lifespan of the remaining non-renewable rock phosphate reserves, but to result in a more efficient, sustainable phosphorus cycle. Solutions include improving the efficiency of fertilizer applications to agricultural land, alongside a better understanding of phosphorus cycling in soil-plant systems, and the interactions between soil physics, chemistry and biology, coupled with plant traits. Opportunities exist for the development of plants that can access different forms of soil phosphorus (e.g., organic phosphorus) and that use internal phosphorus more efficiently. The development of different sources of phosphorus fertilizers are inevitably required given the finite nature of the rock phosphate supplies. Clear opportunities exist, and it is now important that a concerted effort to make advances in phosphorus use efficiency is prioritized.

关键词： organic phosphorus     phosphorus fertilizer     phosphorus use efficiency     rock phosphate    

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Vibration control efficiency of piezoelectric shunt damping system

Dan WU, Zhichun YANG, Hao SUN,

《机械工程前沿（英文）》 2009年 第4卷 第4期   页码 441-446 doi: 10.1007/s11465-009-0055-4

摘要： The piezoelectric shunt damping technique based on the direct piezoelectric effect has been known as a simple, low-lost, lightweight, and easy to implement method for passive damping control of structural vibration. In this technique, a piezoelectric material is used to transform mechanical energy to electrical energy. When applying the piezoelectric shunt damping technique to passively control structural vibration, the piezoelectric materials must be bonded on or embedded in host structure where large strain is induced during vibration, thus to ensure vibrational mechanical energy to be transformed into electrical energy as much as possible. In this paper, the concept of vibration control efficiency of a piezoelectric shunt damping system is proposed and studied theoretically and experimentally. In the study, PZT patches are used as energy converter, and the vibration control efficiency is expressed by the vibration reduction rate per area of the PZT patches. Emphasis is laid on the effect of the generalized electromechanical coupling coefficient on the vibration control efficiency. Four PZT patches with different sizes are bonded on the geometrical central area of four similar clamped aluminum plates, respectively, and vibration control experiments are conducted for these plates using the R-L shunt circuit. The results indicate that the bigger the coupling coefficient , the larger the rate of vibration reduction, and hence, the higher the vibration control efficiency. It also shows that the vibration responses of the first mode of the plates bonded with different PZT patches can be reduced by about 30.5%，48.58%，85.47%, and 89.91%, respectively. It comes to a conclusion that the vibration control efficiency of the piezoelectric shunt damping system decreases with the increase of the area of the PZT patch, whereas the vibration reduction of the plate increases with the area of the PZT patch. Therefore, it is necessary to make topology optimization for the PZT patch in the vibration control utilizing the piezoelectric shunt damping technique.

关键词： piezoelectric shunt     vibration control efficiency     clamped plate     generalized electromechanical coupling coefficient    

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标题 作者 时间 类型 操作

The effect of different agricultural management practices on irrigation efficiency, water use efficiency

La ZHUO, Arjen Y. HOEKSTRA

期刊论文

Evaluating R&D efficiency of China’s listed lithium battery enterprises

期刊论文

Improving the efficiency and effectiveness of global phosphorus use: focus on root and rhizosphere levels

null

期刊论文

Optimization of power and efficiency for an irreversible Diesel heat engine

Shiyan ZHENG, Guoxing LIN

期刊论文

Methods and applications of DEA cross-efficiency: Review and future perspectives

Jie WU, Jiasen SUN, Liang LIANG

期刊论文

STRATEGIES FOR IMPROVING WATER USE EFFICIENCY IN DRYLAND AGROECOSYSTEMS

期刊论文

Effects of dwarfing genes on water use efficiency of bread wheat

Jiakun YAN, Suiqi ZHANG

期刊论文

neutrality potential of wastewater treatment plants: A novel evaluation framework integrating energy efficiency

期刊论文

Approaches to achieve high grain yield and high resource use efficiency in rice

Jianchang YANG

期刊论文

A Comprehensive Evaluation of Policy Effectiveness for Energy Efficiency in Existing Buildings

Xing Wei,Han-ding Guo

期刊论文

Regional characteristics of industrial energy efficiency in China: application of stochastic frontier

Tao HUANG,Akio ONISHI,Feng SHI,Masafumi MORISUGI,Mjo Lwin CHERRY

期刊论文

Genetic study and molecular breeding for high phosphorus use efficiency in maize

null

期刊论文

Energy efficiency and carbon dioxide emissions reduction opportunities in district heating source in

Gaofeng CHEN, Xuejing ZHENG, Lin CONG

期刊论文

Phosphorus use efficiency and fertilizers: future opportunities for improvements

null

期刊论文

Vibration control efficiency of piezoelectric shunt damping system

Dan WU, Zhichun YANG, Hao SUN,

期刊论文