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

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《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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风险矩阵法在武器装备采办风险评估中的运用

李忠民,魏一鸣,汤淑春,陈健

《中国工程科学》 2006年第8卷第6期页码 95-99

摘要：

在对国外广泛采用的风险矩阵评估方法进行全面分析和系统总结的基础上，对风险矩阵方法在我国武器装备采办风险评估中的运用进行了探讨，并从风险影响和风险概率两个准则入手，以某武器型号采办为例示范性地进行了风险评估，从而为制定科学合理的武器装备采办风险管理提供决策依据。

关键词：风险矩阵方法风险评估武器装备采办

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Quality control based on electrode displacement and force in resistance spot welding

Chuntao JI, Lipeng DENG

《机械工程前沿（英文）》 2010年第5卷第4期页码 412-417 doi: 10.1007/s11465-010-0114-x

摘要： The behaviors of electrode displacement and force during spot welding under various conditions, such as different weld currents, electrode forces, and welding times, were studied. Tests were conducted on a 170?kVA MFDC spot welder. Data were collected via a multichannel high-speed data acquisition system and were analyzed with MATLAB. Behaviors of 5182 aluminum and mild steel in spot welding were compared. Results show that nugget expansion rate does not reach zero for aluminium as it does for mild steel as nugget grew to a certain size. A linear relationship is found between the nugget size and maximum expansion that facilitates online weld quality evaluation. An electrode force peak is observed and believed relevant to the sufficient nugget size.

关键词： aluminum electrode displacement electrode force nugget size data acquisition

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Simultaneous acquisition of CT angiography and whole brain CT perfusion images by using multiphase dynamic

Weiwei CHEN, Jianpin QI, Wenzhen ZHU, Wenhua HUANG, Jinmei SONG

《医学前沿（英文）》 2009年第3卷第2期页码 230-235 doi: 10.1007/s11684-009-0023-8

摘要： We implemented a new protocol — multiphase dynamic helical scan to acquire CT angiography (CTA) and whole brain CT perfusion (CTP) images simultaneously with single scan on 16 multidetector CT (MDCT). A total of 90 patients who were randomly assigned into 3 groups were included in our study. Each group underwent CT scan by using the new protocol, traditional CTA and CTP protocol, respectively. The image quality of CTA, the CTP parameter values and the X-ray doses were measured and compared between the new protocol and the traditional protocols. There was no statistically significant difference in the CTA image quality between the above methods ( =0.55). For CTP parameters, the new protocol tended to overestimate the blood volume (BV) and blood flow (BF) value, and to underestimate the mean transit time (MTT) value compared with the traditional method. However, there was no statistically significant difference in BV, BF, and MTT value between the two methods except permeability surface (PS) ( >0.05). The volume CT dose index (CTDIvol) and dose length product (DLP) of our protocol were lower than the traditional one. The new protocol can obtain valuable diagnostic information in a shorter time without significant compromise in image quality. In addition, it reduces the radiation dose as well as contrast medium usage on the patient.

关键词： computed tomography angiography computed tomography perfusion

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基于全寿命周期的武器装备采办风险识别研究

李忠民,,汤淑春,李军4,陈健

《中国工程科学》 2005年第7卷第12期页码 49-53

摘要：

讨论了武器装备采办全寿命周期的概念，给出了武器装备采办全寿命周期风险识别的原则和程序；探讨了采办风险识别的方法，提出了全寿命周期各阶段风险识别方法的组合选择方案；在寿命周期各阶段识别方法的选择方案基础上，分析了寿命周期各阶段的风险，为武器装备采办全寿命周期风险的系统管理奠定了基础。

关键词：风险识别武器装备采办风险管理全寿命周期

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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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多孔径光学成像系统及其光场采集数学模型 Review Article

祁启明,傅瑞罡,邵铮铮,王平,范红旗

《信息与电子工程前沿（英文）》 2022年第23卷第6期页码 823-844 doi: 10.1631/FITEE.2100058

摘要：

受昆虫复眼启发，为提高光学成像质量，如获得高分辨率图像或大视场图像，研究者提出了许多多孔径光学成像系统。光场采集数学模型是联系多孔径光学成像系统结构设计与应用的纽带，但光场采集数学模型较少被关注。本文系统梳理了典型多孔径光学成像系统（仿生复眼、光场相机、相机阵列），总结了不同结构下多孔径光学成像系统的一般性光场采集数学模型。列出的数学模型既可用于计算特定多孔径光学成像系统的关键指标，如视场大小和子图像重叠比等，也可作为数学工具，便于研究者完成对成像系统的定量设计与评估。

关键词：多孔径光学成像系统；仿生复眼；光场相机；相机阵列；光场采集模型

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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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Analysis and control of micro-stepping characteristics of ultrasonic motor

Ning CHEN, Jieji ZHENG, Xianliang JIANG, Shixun FAN, Dapeng FAN

《机械工程前沿（英文）》 2020年第15卷第4期页码 585-599 doi: 10.1007/s11465-019-0577-3

摘要： Micro-stepping motion of ultrasonic motors satisfies biomedical applications, such as cell operation and nuclear magnetic resonance, which require a precise compact-structure non-magnetization positioning device. When the pulse number is relatively small, the stopping characteristics have a non-negligible effect on the entire stepwise process. However, few studies have been conducted to show the rule of the open-loop stepwise motion, especially the shutdown stage. In this study, the modal differences of the shutdown stage are found connected with amplitude and velocity at the turn-off instant. Changes of the length in the contact area and driving zone as well as the input currents, vibration states, output torque, and axial pressure are derived by a simulation model to further explore the rules. The speed curves and vibration results in functions of different pulse numbers are compared, and the stepwise motion can be described by a two-stage two-order transfer function. A test workbench based on the Field Programmable Gate Array is built for acquiring the speed, currents, and feedback voltages of the startup–shutdown stage accurately with the help of its excellent synchronization performances. Therefore, stator vibration, rotor velocity, and terminal displacements under different pulse numbers can be compared. Moreover, the two-stage two-order model is identified on the stepwise speed curves, and the fitness over 85% between the simulation and test verifies the model availability. Finally, with the optimization of the pulse number, the motor achieves 3.3 µrad in clockwise and counterclockwise direction.

关键词： ultrasonic motor stepping characteristics pulse number control synchronous acquisition system precise positioning