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Allocation of grassland, livestock and arable based on the spatial and temporal analysis for food demand

Huilong LIN, Ruichao LI, Yifan LIU, Jingrong ZHANG, Jizhou REN

《农业科学与工程前沿（英文）》 2017年 第4卷 第1期   页码 69-80 doi: 10.15302/J-FASE-2017140

摘要： To explore the distribution of food demand and the projected trend in future food demand in China, this paper analyzed the change in current (1998–2012) per-capita demand for grain, grain-consuming and herbivorous livestock products, and predicted the food demand in 2020. The results indicated that in 1998–2012, the national per-capita consumption of grain ration declined by about 36.66%, and the per-capita consumption of grain-consu-ming and herbivorous livestock products increased by about 48% and 34.09%, respectively. The grain-consu-ming livestock products have become the primary source of both calories and protein for consumers. The proportion of herbivorous livestock products in consumer diets has increased steadily and there has been huge potential in substituting beef and mutton for pork in this dynamic market. The demand for food in different provinces of China is highly variable, which is important for planning grassland agriculture development and ensuring food safety. The demand for grain, and grain-consuming and herbivorous livestock products will increase by about 3.3%, 20% and 14% respectively by 2020. Based on the food demand and trend in the development of grassland agriculture, the 31 provinces in China are divided into three priority groups for grassland agriculture development.

关键词： arable land equivalent unit (ALEU)     food equivalent unit (FEU)     food security     grassland agriculture     time trend prediction    

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Cadmium pollution from phosphate fertilizers in arable soils and crops: an overview

null

《农业科学与工程前沿（英文）》 2019年 第6卷 第4期   页码 419-430 doi: 10.15302/J-FASE-2019273

摘要：

The application of mineral and organic phosphorus fertilizers to arable land has greatly increased crop yield to meet the world food demand. On the other hand, impurities in these fertilizers, such as heavy metals, are being added to agricultural soils, resulting both from the raw materials themselves and the processes used to obtain the final product. Cadmium, a non-essential and toxic heavy metal, has been found in relatively high amounts in common P fertilizers obtained from sediments. This metal poses a high risk for soil fertility, crop cultivation, and plants in general. Furthermore, human health might be compromised by the cadmium concentrations in agricultural and livestock products, due to the bioaccumulation effect in the food web. The accumulation in the different matrixes is the result of the high mobility and flexible availability of this harmful metal. This review summarizes risks to human health, the factors influencing cadmium movement in soils and crop uptake, as well as common plant responses to its toxicity. In addition, it summarizes cadmium balances in soils, trends, long-term experiments, and further studies. Cadmium inputs and outputs in arable soil, together with their calculated concentrations, are compared between two different regions: the European countries (in particular Germany) and China. The comparison appears useful because of the different proportions in the inputs and outputs of cadmium, and the diverse geographical, environmental and social factors. Moreover, these variables and their influences on cadmium contamination improve the understanding of the pollution from phosphate fertilizers and will help to establish future mitigation policies.

关键词： soil pollution     arable land     crop production     cadmium balance     P fertilizer     cadmium toxicity    

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China’s new problems of food security revealed by the Food Equivalent Unit

Huilong LIN,Ruichao LI,Cangyu JIN,Chong WANG,Maohong WEI,Jizhou REN

《农业科学与工程前沿（英文）》 2014年 第1卷 第1期   页码 69-76 doi: 10.15302/J-FASE-2014023

摘要： China's food security has a great influence on the world, and has always been the top priority in China. In recent years, as the concept of food security is evolving into one of nutrition security and the importance of food diversity is increasing, research based on nutrition security and broad food systems are increasingly needed in today’s China. Thus, not only grain for human consumption, but also animal foods have been integrated into the Food Equivalent, which is used to analyze China’s current agriculture system and reveal the water resource distribution. The results indicated that the average animal food consumption has risen by 78.6%, and now China’s daily supply of animal food per capita has reached about 50% of that in the USA and 80% of that in the South Korea. So there exist an obvious disparity in animal food supply between China and these two countries. It is impossible for the China’s current agricultural system to achieve the level in the USA. Under China’s current agricultural system, the consumption proportion of feed grain had surpassed the consumption of food grain, increased sharply from 33% in 1992 to 67% in 2011. However, the growth potential of total grain output is approaching an upper limit, so the continued growth of feed grain demand exerts great pressure on the China’s food supply. The discordance of the spatial distribution of water resource and virtual water revealed that China’s current agriculture system had a low efficiency in being able to achieve food and nutrition security. China’s current “grain farming” cannot meet the demand of increasing nutrition and appropriate resource utilization. The implementation of grassland agriculture appears feasible and necessary for saving feed grain, providing a large number of high-quality animal foods and appropriate water resource utilization.

关键词： food security     nutrition security     food equivalent unit     grassland agriculture     China    

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THE 4C APPROACH AS A WAY TO UNDERSTAND SPECIES INTERACTIONS DETERMINING INTERCROPPING PRODUCTIVITY

《农业科学与工程前沿（英文）》 2021年 第8卷 第3期   页码 387-399 doi: 10.15302/J-FASE-2021414

摘要：

Modern agriculture needs to develop transition pathways toward agroecological, resilient and sustainable farming systems. One key pathway for such agroecological intensification is the diversification of cropping systems using intercropping and notably cereal-grain legume mixtures. Such mixtures or intercrops have the potential to increase and stabilize yields and improve cereal grain protein concentration in comparison to sole crops. Species mixtures are complex and the 4C approach is both a pedagogical and scientific way to represent the combination of four joint effects of Competition, Complementarity, Cooperation, and Compensation as processes or effects occurring simultaneously and dynamically between species over the whole cropping cycle. Competition is when plants have fairly similar requirements for abiotic resources in space and time, the result of all processes that occur when one species has a greater ability to use limiting resources (e.g., nutrients, water, space, light) than others. Complementarity is when plants grown together have different requirements for abiotic resources in space, time or form. Cooperation is when the modification of the environment by one species is beneficial to the other(s). Compensation is when the failure of one species is compensated by the other(s) because they differ in their sensitivity to abiotic stress. The 4C approach allows to assess the performance of arable intercropping versus classical sole cropping through understanding the use of abiotic resources.

 

关键词： compensation     competition     complementarity     cooperation     interspecific interactions     land equivalent ratio     light     nutrients     species mixtures     water    

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Eddy current measurement of the thickness of top Cu film of the multilayer interconnects in the integrated circuit (IC) manufacturing process

Zilian QU,Yonggang MENG,Qian ZHAO

《机械工程前沿（英文）》 2015年 第10卷 第1期   页码 1-6 doi: 10.1007/s11465-015-0325-2

摘要：

This paper proposes a new eddy current method, named equivalent unit method (EUM), for the thickness measurement of the top copper film of multilayer interconnects in the chemical mechanical polishing (CMP) process, which is an important step in the integrated circuit (IC) manufacturing. The influence of the underneath circuit layers on the eddy current is modeled and treated as an equivalent film thickness. By subtracting this equivalent film component, the accuracy of the thickness measurement of the top copper layer with an eddy current sensor is improved and the absolute error is 3 nm for sampler measurement.

关键词： CMP     eddy current     multilayer wafer     Cu interconnects     equivalent unit    

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面向 2050 年我国农业资源平衡与国际进口潜力研究

郑海霞,尤飞,罗其友,唐华俊

《中国工程科学》 2022年 第24卷 第1期   页码 20-28 doi: 10.15302/J-SSCAE-2022.01.003

摘要：

受农业高质量发展、食物消费结构转型升级、气候变化的多重影响，我国农业资源供需平衡日益趋紧，因而统筹利用国际国内两种资源、两个市场，保障我国中长期粮食安全至关重要。本文在对比分析国内、国际农业资源的基础上，研究了我国2035 年和2050 年的粮食消费需求、消费结构、供给结构，分析了未来农业资源供需缺口以及虚拟水、虚拟耕地的可进口潜力与进口来源地，据此展望了我国农业水土资源利用的目标。研究表明：我国虚拟耕地进口将在2048 年前后达到峰值，需进口虚拟耕地近6.147×107 hm2；虚拟水进口量在2045 年前后达到峰值，虚拟水进口量为1.136×108 m3（以蓝水估算），约为2017 年全国农业总用水量的30%；可增加的耕地进口潜力主要来自南美洲和非洲。

关键词： 农业资源平衡     食物消费结构     虚拟水     虚拟耕地     进口潜力    

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AGRONOMIC AND ENVIRONMENTAL BENEFITS OF REINTRODUCING HERB- AND LEGUME-RICH MULTISPECIES LEYS INTO ARABLE

《农业科学与工程前沿（英文）》 2022年 第9卷 第2期   页码 245-271 doi: 10.15302/J-FASE-2021439

摘要：

Agricultural intensification and the subsequent decline of mixed farming systems has led to an increase in continuous cropping with only a few fallow or break years, undermining global soil health. Arable-ley rotations incorporating temporary pastures (leys) lasting 1–4 years may alleviate soil degradation by building soil fertility and improving soil structure. However, the majority of previous research on arable-ley rotations has utilized either grass or grass-clover leys within ungrazed systems. Multispecies leys, containing a mix of grasses, legumes, and herbs, are rapidly gaining popularity due to their promotion in agri-environment schemes and potential to deliver greater ecosystem services than conventional grass or grass-clover leys. Livestock grazing in arable-ley rotations may increase the economic resilience of these systems, despite limited research of the effects of multispecies leys on ruminant health and greenhouse gas emissions. This review aims to evaluate previous research on multispecies leys, highlighting areas for future research and the potential benefits and disbenefits on soil quality and livestock productivity. The botanical composition of multispecies leys is crucial, as legumes, deep rooted perennial plants (e.g., Onobrychis viciifolia and Cichorium intybus) and herbs (e.g., Plantago lanceolata) can increase soil carbon, improve soil structure, reduce nitrogen fertilizer requirements, and promote the recovery of soil fauna (e.g., earthworms) in degraded arable soils while delivering additional environmental benefits (e.g., biological nitrification inhibition and enteric methane reduction). Multispecies leys have the potential to deliver biologically driven regenerative agriculture, but more long-term research is needed to underpin evidence-based policy and farmer guidance.

关键词： bioactive forages / integrated crop-livestock systems / nitrogen cycling / plant secondary metabolites / soil carbon / soil quality    

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A modified zone model for estimating equivalent room thermal capacity

Hua CHEN, Xiaolin WANG

《能源前沿（英文）》 2013年 第7卷 第3期   页码 351-357 doi: 10.1007/s11708-013-0254-x

摘要： The zone model has been widely applied in control analysis of heating, ventilation and air conditioning (HVAC) systems to achieve a high building efficiency. This paper proposed a modified zone model which is much simpler in the HVAC system simulation and has the similar accuracy to the complicated simulation model. The proposed model took into consideration the effect of envelop heat reservoir on the room indoor temperature by introducing the thermal admittance of the inner surfaces of the building enclosure. The thermal admittance for the building enclosure was developed based on the building thermal network analytical theory and transfer function method. The efficacy of the proposed model was demonstrated by comparing it with the complicated model — heat balance method (HTB2 program). The predicted results from the proposed model well agreed with those from the complicated simulation. The proposed model can then make the HVAC system dynamic simulation much faster and more acceptable for control design due to its simplicity and efficiency.

关键词： room model     thermal network analysis     transfer function     heating     ventilation and air conditioning (HVAC) system simulation    

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Distribution of background equivalent static wind load on high-rise buildings

Jianguo ZHANG , Ming GU ,

《结构与土木工程前沿（英文）》 2009年 第3卷 第3期   页码 241-248 doi: 10.1007/s11709-009-0036-z

摘要： In this paper, the along-wind and cross-wind fluctuating load distributions along the height of high-rise buildings and their correlations are obtained through simultaneous pressure measurements in a wind tunnel. Some typical methods proposed in some relative literatures, i.e., load-response correlation (LRC), and quasi-mean load (QML) and gust load envelope (GLE) methods, are verified in terms of their accuracy in describing the background equivalent static wind load distribution on high-rise buildings. Based on the results, formulae of the distribution of background equivalent static load on high-rise buildings with typical shapes are put forward. It is shown that these formulae are of high accuracy and practical use.

关键词： high-rise buildings     along-wind     cross-wind     background equivalent static wind load     close formulae    

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Equivalent circuit and characteristic simulation of a brushless electrically excited synchronous wind

Hao WANG, Fengge ZHANG, Tao GUAN, Siyang YU

《机械工程前沿（英文）》 2017年 第12卷 第3期   页码 420-426 doi: 10.1007/s11465-017-0439-9

摘要：

A brushless electrically excited synchronous generator (BEESG) with a hybrid rotor is a novel electrically excited synchronous generator. The BEESG proposed in this paper is composed of a conventional stator with two different sets of windings with different pole numbers, and a hybrid rotor with powerful coupling capacity. The pole number of the rotor is different from those of the stator windings. Thus, an analysis method different from that applied to conventional generators should be applied to the BEESG. In view of this problem, the equivalent circuit and electromagnetic torque expression of the BEESG are derived on the basis of electromagnetic relation of the proposed generator. The generator is simulated and tested experimentally using the established equivalent circuit model. The experimental and simulation data are then analyzed and compared. Results show the validity of the equivalent circuit model.

关键词： wind power     brushless electrically excited synchronous generator     hybrid rotor     equivalent circuit    

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A solution to stochastic unit commitment problem for a wind-thermal system coordination

B. SARAVANAN,Shreya MISHRA,Debrupa NAG

《能源前沿（英文）》 2014年 第8卷 第2期   页码 192-200 doi: 10.1007/s11708-014-0306-x

摘要： Unit commitment (UC) problem is one of the most important decision making problems in power system. In this paper the UC problem is solved by considering it as a real time problem by adding stochasticity in the generation side because of wind-thermal co-ordination system as well as stochasticity in the load side by incorporating the randomness of the load. The most important issue that needs to be addressed is the achievement of an economic unit commitment solution after solving UC as a real time problem. This paper proposes a hybrid approach to solve the stochastic unit commitment problem considering the volatile nature of wind and formulating the UC problem as a chance constrained problem in which the load is met with high probability over the entire time period.

关键词： unit commitment (UC)     randomness     wind generation     univariate     chance constrained    

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Solving unit commitment problem using a novel version of harmony search algorithm

Roozbeh MORSALI,Tohid JAFARI,Amirhossein GHODS,Mohammad KARIMI

《能源前沿（英文）》 2014年 第8卷 第3期   页码 297-304 doi: 10.1007/s11708-014-0309-7

摘要： In this context, a novel structure was proposed for improving harmony search (HS) algorithm to solve the unit comment (UC) problem. The HS algorithm obtained optimal solution for defined objective function by improvising, updating and checking operators. In the proposed improved self-adaptive HS (SGHS) algorithm, two important control parameters were adjusted to reach better solution from the simple HS algorithm. The objective function of this study consisted of operation, start-up and shut-down costs. To confirm the effectiveness, the SGHS algorithm was tested on systems with 10, 20, 40 and 60 generating units, and the obtained results were compared with those of the simple HS algorithm and other related works.

关键词： generation scheduling     harmony search (HS) algorithm     intelligent technique     unit commitment    

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A solution to the unit commitment problem—a review

B. SARAVANAN, Siddharth DAS, Surbhi SIKRI, D. P. KOTHARI

《能源前沿（英文）》 2013年 第7卷 第2期   页码 223-236 doi: 10.1007/s11708-013-0240-3

摘要： Unit commitment (UC) is an optimization problem used to determine the operation schedule of the generating units at every hour interval with varying loads under different constraints and environments. Many algorithms have been invented in the past five decades for optimization of the UC problem, but still researchers are working in this field to find new hybrid algorithms to make the problem more realistic. The importance of UC is increasing with the constantly varying demands. Therefore, there is an urgent need in the power sector to keep track of the latest methodologies to further optimize the working criterions of the generating units. This paper focuses on providing a clear review of the latest techniques employed in optimizing UC problems for both stochastic and deterministic loads, which has been acquired from many peer reviewed published papers. It has been divided into many sections which include various constraints based on profit, security, emission and time. It emphasizes not only on deregulated and regulated environments but also on renewable energy and distributed generating systems. In terms of contributions, the detailed analysis of all the UC algorithms has been discussed for the benefit of new researchers interested in working in this field.

关键词： unit commitment (UC)     optimization     deterministic load     stochastic load     evolutionary programming (EP)     hybrid    

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Exploring differentiated improvement strategies of cultivated land quality in China

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023523

摘要：

● Cultivated land quality can be considered in four dimensions: suitability, contiguity, resistance, and ecological stress.

关键词： China     cultivated land quality     differentiated improvement     food security    

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Fault classification and reconfiguration of distribution systems using equivalent capacity margin method

K. Sathish KUMAR, T. JAYABARATHI

《能源前沿（英文）》 2012年 第6卷 第4期   页码 394-402 doi: 10.1007/s11708-012-0211-0

摘要： This paper investigates the capability of support vector machines (SVM) for prediction of fault classification and the use of the concept of equivalent capacity margin (ECM) for restoration of the power system. The SVM, as a novel type of machine learning based on statistical learning theory, achieves good generalization ability by adopting a structural risk minimization (SRM) induction principle aimed at minimizing a bound on the generalization error of a model rather than the minimization of the error on the training data only. Here, the SVM has been used as a classification. The inputs of the SVM model are power and voltage values. An equation has been developed for the prediction of the fault in the power system based on the developed SVM model. The next steps of this paper are the restoration and reconfiguration by using the ECM concept, the development of a code, and the testing of the results with various load outages, which have been executed for a 12 load system.

关键词： support vector machines (SVM)     structural risk minimization (SRM)     equivalent capacity margin (ECM)     restoration     fault classification    

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标题 作者 时间 类型 操作

Allocation of grassland, livestock and arable based on the spatial and temporal analysis for food demand

Huilong LIN, Ruichao LI, Yifan LIU, Jingrong ZHANG, Jizhou REN

期刊论文

Cadmium pollution from phosphate fertilizers in arable soils and crops: an overview

null

期刊论文

China’s new problems of food security revealed by the Food Equivalent Unit

Huilong LIN,Ruichao LI,Cangyu JIN,Chong WANG,Maohong WEI,Jizhou REN

期刊论文

THE 4C APPROACH AS A WAY TO UNDERSTAND SPECIES INTERACTIONS DETERMINING INTERCROPPING PRODUCTIVITY

期刊论文

Eddy current measurement of the thickness of top Cu film of the multilayer interconnects in the integrated circuit (IC) manufacturing process

Zilian QU,Yonggang MENG,Qian ZHAO

期刊论文

面向 2050 年我国农业资源平衡与国际进口潜力研究

郑海霞,尤飞,罗其友,唐华俊

期刊论文

AGRONOMIC AND ENVIRONMENTAL BENEFITS OF REINTRODUCING HERB- AND LEGUME-RICH MULTISPECIES LEYS INTO ARABLE

期刊论文

A modified zone model for estimating equivalent room thermal capacity

Hua CHEN, Xiaolin WANG

期刊论文

Distribution of background equivalent static wind load on high-rise buildings

Jianguo ZHANG , Ming GU ,

期刊论文

Equivalent circuit and characteristic simulation of a brushless electrically excited synchronous wind

Hao WANG, Fengge ZHANG, Tao GUAN, Siyang YU

期刊论文

A solution to stochastic unit commitment problem for a wind-thermal system coordination

B. SARAVANAN,Shreya MISHRA,Debrupa NAG

期刊论文

Solving unit commitment problem using a novel version of harmony search algorithm

Roozbeh MORSALI,Tohid JAFARI,Amirhossein GHODS,Mohammad KARIMI

期刊论文

A solution to the unit commitment problem—a review

B. SARAVANAN, Siddharth DAS, Surbhi SIKRI, D. P. KOTHARI

期刊论文

Exploring differentiated improvement strategies of cultivated land quality in China

期刊论文

Fault classification and reconfiguration of distribution systems using equivalent capacity margin method

K. Sathish KUMAR, T. JAYABARATHI

期刊论文