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Estimation of optimum design of structural systems via machine learning
Frontiers of Structural and Civil Engineering 2021, Volume 15, Issue 6, Pages 1441-1452 doi: 10.1007/s11709-021-0774-0
Keywords： optimization metaheuristic algorithms harmony search structural designs machine learning artificial
CROP DIVERSITY AND SUSTAINABLE AGRICULTURE: MECHANISMS, DESIGNS AND APPLICATIONS
Frontiers of Agricultural Science and Engineering 2021, Volume 8, Issue 3, Pages 359-361 doi: 10.15302/J-FASE -2021417
Intensive monoculture agriculture has contributed greatly to global food supply over many decades, but the excessive use of agricultural chemicals (fertilizers, herbicides and pesticides) and intensive cultivation systems has resulted in negative side effects, such as soil erosion, soil degradation, and non-point source pollution[1]. To many observers, agriculture looms as a major global threat to nature conservation and biodiversity. As noted in the Global Biodiversity Outlook 4[2], the drivers associated with food systems and agriculture account for around 70% and 50% of the projected losses by 2050 of terrestrial and freshwater biodiversity, respectively[3].
In addition, agricultural development and modernization of agriculture has led to a decline in the total number of plant species upon which humans depend for food[4]. Currently, fewer than 200 of some 6000 plant species grown for food contribute substantially to global food output, and only nine species account for 67% of total crop production[3]. The global crop diversity has declined in past decades.
Crop species diversity at a national scale was identified as one of the most important factors that stabilize grain production at a national level[5]. A group of long-term field experiments demonstrated that crop diversity also stabilizes temporal grain productivity at field level[6]. Therefore, maintaining crop diversity at both national and field levels is of considerable importance for food security at national and global scales.
Crop diversity includes temporal (crop rotation) and spatial diversity (e.g., intercropping, agroforestry, cultivar mixtures and cover crops) at field scale. Compared to intensive monocultures, diversified cropping systems provide additional options to support multiple ecosystem functions. For instance, crop diversity may increase above- and belowground biodiversity, improve yield stability, reduce pest and disease damage, reduce uses of chemicals, increase the efficiency of the use land, light water and nutrient resources, and enhance stress resilience in agricultural systems.
To highlight advances in research and use of crop diversity, from developing and developed countries, we have prepared this special issue on “Crop Diversity and Sustainable Agriculture” for Frontiers of Agricultural Sciences and Engineering, mainly focusing on intercropping.
Intercropping, growing at least two crops at the same time as a mixture, for example, in alternate rows or strips, is one effective pathway for increasing crop diversity at the field scale. Over recent decades, there have been substantial advances in terms of understanding of processes between intercropped species and applications in practice. There are 10 articles in this special issue including letters, opinions, review and research articles with contributions from Belgium, China, Denmark, France, Germany, Greece, Italy, the Netherlands, Spain, Switzerlands, UK, and Mexico etc.
The contributors are internationally-active scientists and agronomists contributing to intercropping research and extension. For example, Antoine Messean is coordinator of the EU H2020 Research project DiverIMPACTS “Diversification through rotation, intercropping, multiple cropping, promoted with actors and value chains towards sustainability”. Eric Justes is coordinator of the EU H2020 Research project ReMIX “Redesigning European cropping systems based on species mixtures”. Maria Finckh has worked on crop cultivar mixture and organic agriculture over many years. Henrik Hauggaard-Nielsen has outstanding expertise in intercropping research and applications, moving from detailed studies on species interactions in intercropping to working with farmers and other stakeholders to make intercropping work in practical farming. In addition to these established scientists, young scientists who have taken an interest in intercropping also contribute to the special issue, including Wen-Feng Cong, Yixiang Liu, Qi Wang, Hao Yang and others.
The first contribution to this special issue addresses how to design cropping systems to reach crop diversification, with Wen-Feng Cong and coworkers ( https://doi.org/10.15302/J-FASE-2021392) considering that it is necessary to optimize existing and/or design novel cropping systems based on farming practices and ecological principles, and to strengthen targeted ecosystem services to achieve identified objectives. In addition, the design should consider regional characteristics with the concurrent objectives of safe, nutritious food production and environmental protection.
The benefits of crop diversification have been demonstrated in many studies. Wen-Feng Cong and coworkers describe the benefits of crop diversification at three scales: field, farm, and landscape. Hao Yang and coauthors reviewed the multiple functions of intercropping. Intercropping enhances crop productivity and its stability, it promotes efficient use of resources and saves mineral fertilizer, controls pests and diseases of crops and reduces the use of pesticides. It mitigates climate change by sequestering carbon in soil, reduces non-point source pollution, and increases above- and belowground biodiversity of other taxa at field scale ( https://doi.org/10.15302/J-FASE-2021398).
Eric Justes and coworkers proposed the “4C” framework to help understand the role of species interactions in intercropping ( https://doi.org/10.15302/J-FASE-2021414). The four components are competition, complementary, cooperation (facilitation) and compensation, which work often simultaneously in intercropping. Hao Yang and coworkers used the concept of diversity effect from ecology to understand the contribution of complementarity and selection effects to enhanced productivity in intercropping. The complementarity effect consists of interspecific facilitation and niche differentiation between crop species, whereas the selection effect is mainly derived from competitive processes between species such that one species dominates the other ( https://doi.org/10.15302/J-FASE-2021398). Also, Luis Garcia-Barrios and Yanus A. Dechnik-Vazquez dissected the ecological concept of the complementarity and selection effects to develop a relative multicrop resistance index to analyze the relation between higher multicrop yield and land use efficiency and the different ecological causes of overyielding under two contrasting water stress regimes ( https://doi.org/10.15302/J-FASE-2021412).
Odette Denise Weedon and Maria Renate Finckh found that composite cross populations, with different disease susceptibilities of three winter wheat cultivars, were moderately resistant to brown rust and even to the newly emerged stripe rust races prevalent in Europe since 2011, but performance varied between standard and organic management contexts ( https://doi.org/10.15302/J-FASE-2021394).
Comparing the performance of intercrops and sole crops is critical to make a sound evaluation of the benefits of intercropping and assess interactions between species choice, intercrop design, intercrop management and factors related to the production situation and pedoclimatic context. Wopke van der Werf and coworkers review some of the metrics that could be used in the quantitative synthesis of literature data on intercropping ( https://doi.org/10.15302/J-FASE-2021413).
Interspecific interactions provide some of the advantages of intercropping, and can be divided into above- and belowground interactions. Aboveground interactions can include light and space competition, which is influenced by crop species traits. Root exudates are also important in interspecific interactions between intercropped or rotated species. Qi Wang and coworkers estimated the light interception of growth stage of maize-peanut intercropping and corresponding monocultures, and found that intercropping has higher light interception than monoculture, and increasing plant density did not further increase light interception of intercropping ( https://doi.org/10.15302/J-FASE-2021403). Yuxin Yang and coworkers reported that the root exudates of fennel (Foeniculum vulgare) can reduce infection of tobacco by Phytophthora nicotianae via inhibiting the motility and germination of the spores of the pathogen ( https://doi.org/10.15302/J-FASE-2021399).
Focusing on the application of intercropping, Wen-Feng Cong and coworkers formulated species recommendations for different regions of China for different crop diversity patterns and crop species combinations. These authors also suggested three steps for implementing crop diversification on the North China Plain. Although there are multiple benefits of crop diversification, its extension and application are hindered by various technical, organizational, and institutional barriers along value chains, especially in Europe. Based on the findings of the European Crop Diversification Cluster projects, Antoine Messéan and coworkers suggested that there needs to be more coordination and cooperation between agrifood system stakeholders, and establish multiactor networks, toward an agroecological transition of European agriculture ( https://doi.org/10.15302/J-FASE-2021406). In addition, Henrik Hauggaard-Nielsen and coworkers report the outcomes of a workshop for participatory research to overcome the barriers to enhanced coordination and networking between stakeholders ( https://doi.org/10.15302/J-FASE-2021416).
Intercropping, though highly effective in labor-intensive agriculture, may be difficult to implement in machine-intensive, large-scale modern agriculture because appropriate large equipment is not commercially available for planting and harvesting various crop mixtures grown with strip intercropping[6]. Thus, the appropriate machinery will need to be developed for further practical application in large-scale agriculture.
As the guest editors, we thank all the authors and reviewers for their great contributions to this special issue on “Crop Diversity and Sustainable Agriculture”. We also thank the FASE editorial team for their kind supports.
Optimization of spatial structure designs of control rod using Monte Carlo code RMC
Frontiers in Energy 2021, Volume 15, Issue 4, Pages 974-983 doi: 10.1007/s11708-021-0769-5
Keywords： control rod optimized spatial structure neutronic performance burnup stability
Implicit Heaviside filter with high continuity based on suitably graded THB splines
Frontiers of Mechanical Engineering 2022, Volume 17, Issue 1, Pages 14-14 doi: 10.1007/s11465-021-0670-2
Keywords： topology optimization truncated hierarchical B-spline isogeometric analysis black and white designs
Designs and practices of energy saving in Lhasa Railway Station
Kai CUI, Yungang PAN, Lixin SHAN,
Frontiers in Energy 2010, Volume 4, Issue 1, Pages 106-116 doi: 10.1007/s11708-010-0011-3
Keywords： building energy saving natural ventilation solar energy radiant floor heating
Approximation of structural damping and input excitation force
Mohammad SALAVATI
Frontiers of Structural and Civil Engineering 2017, Volume 11, Issue 2, Pages 244-254 doi: 10.1007/s11709-016-0371-9
Keywords： structural modal parameters damping identification method input excitation force identification Inverse
Planning and Design on Windproof and Desert Controlsof Railway Engineering
Jiang Fuqiang,Wang Xilai
Strategic Study of CAE 2007, Volume 9, Issue 5, Pages 7-10
结合国家西部大开发的有关方针政策，论述了在新形势下铁路防风治沙工程规划设计的新型指导思 想；从人与自然和谐发展角度，对铁路防风治沙工程的规划设计提出了几点合理化建议；对目前规划设计中存 在的固沙防火带宽度和沙障立柱埋深计算问题，从理论上进行了探讨并提出了解决方案。对于新形势下的铁路 防风治沙工程具有一定的指导意义和现实意义。
Keywords： railroad wind-breaking and desert-control plan designs
Design and simulation of a cable-pulley-based transmission for artificial ankle joints
Huaxin LIU,Marco CECCARELLI,Qiang HUANG
Frontiers of Mechanical Engineering 2016, Volume 11, Issue 2, Pages 170-183 doi: 10.1007/s11465-016-0383-0
In this paper, a mechanical transmission based on cable pulley is proposed for human-like actuation in the artificial ankle joints of human-scale. The anatomy articular characteristics of the human ankle is discussed for proper biomimetic inspiration in designing an accurate, efficient, and robust motion control of artificial ankle joint devices. The design procedure is presented through the inclusion of conceptual considerations and design details for an interactive solution of the transmission system. A mechanical design is elaborated for the ankle joint angular with pitch motion. A multi-body dynamic simulation model is elaborated accordingly and evaluated numerically in the ADAMS environment. Results of the numerical simulations are discussed to evaluate the dynamic performance of the proposed design solution and to investigate the feasibility of the proposed design in future applications for humanoid robots.
Keywords： biomimetic designs ankle joints cable-pulley transmissions multi-body dynamic simulation numerical characterization
Effects of green roof damping and configuration on structural seismic response
Frontiers of Structural and Civil Engineering Pages 1133-1144 doi: 10.1007/s11709-023-0959-9
Keywords： green infrastructure green roof structural resilience seismic design
Xinqun ZHU, Hong HAO
Frontiers of Structural and Civil Engineering 2012, Volume 6, Issue 3, Pages 321-333 doi: 10.1007/s11709-012-0161-y
Keywords： integrated structural health monitoring operational conditions vibration and guided wave
Digital image correlation-based structural state detection through deep learning
Frontiers of Structural and Civil Engineering 2022, Volume 16, Issue 1, Pages 45-56 doi: 10.1007/s11709-021-0777-x
Keywords： structural state detection deep learning digital image correlation vibration signal steel frame
Ali KARIMPOUR, Salam RAHMATALLA
Frontiers of Structural and Civil Engineering 2020, Volume 14, Issue 6, Pages 1331-1348 doi: 10.1007/s11709-020-0686-4
Keywords： structural model validation eigenvalue problem response surface inverse problems
Advanced analysis for structural steel building design
CHEN Wai Fah
Frontiers of Structural and Civil Engineering 2008, Volume 2, Issue 3, Pages 189-196 doi: 10.1007/s11709-008-0024-8
Keywords： building Specifications comprehensive introduction structural resistance traditional
Gholamreza ABDOLLAHZADEH, Hadi FAGHIHMALEKI
Frontiers of Structural and Civil Engineering 2018, Volume 12, Issue 3, Pages 425-437 doi: 10.1007/s11709-017-0427-5
Keywords： gas blast pushdown analysis progressive collapse annual probability of structural collapse 3D model of
Stress-strain relationship with soil structural parameters of collapse loess
SHAO Shengjun, LONG Jiyong, YU Qinggao
Frontiers of Structural and Civil Engineering 2008, Volume 2, Issue 2, Pages 151-160 doi: 10.1007/s11709-008-0020-z
Keywords： hardening shearing expansion unsaturated structural property mathematical expression
Title Author Date Type Operation
Designs and practices of energy saving in Lhasa Railway Station
Kai CUI, Yungang PAN, Lixin SHAN,
Journal Article
Planning and Design on Windproof and Desert Controlsof Railway Engineering
Jiang Fuqiang,Wang Xilai
Journal Article
Design and simulation of a cable-pulley-based transmission for artificial ankle joints
Huaxin LIU,Marco CECCARELLI,Qiang HUANG
Journal Article
Development of an integrated structural health monitoring system for bridge structures in operational
Xinqun ZHU, Hong HAO
Journal Article
Identification of structural parameters and boundary conditions using a minimum number of measurement
Ali KARIMPOUR, Salam RAHMATALLA
Journal Article
Proposal of a probabilistic assessment of structural collapse concomitantly subject to earthquake and
Gholamreza ABDOLLAHZADEH, Hadi FAGHIHMALEKI
Journal Article
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