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Research and Design of Consistent Project Cases for the Software Engineering Course Group
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作者 Junwei Du Guozhu Liu +3 位作者 Quan Liu Xinglu Ma Meijiao Xu Wenfeng Liu 《计算机教育》 2023年第12期94-105,共12页
In order to enhance the abilities of practical innovation and solving complex engineering problems of students in the engineering context,we design a course cluster teaching model based on a unified enterprise-level p... In order to enhance the abilities of practical innovation and solving complex engineering problems of students in the engineering context,we design a course cluster teaching model based on a unified enterprise-level project case.The program divides the knowledge points required by the project into the corresponding courses,and divides their realization into the practical teaching cases,so as to realize the design of teaching practice cases embodied in the unified project framework.This model allows students to practice projects based on the unified project background while learning knowledge from different courses.It not only allows students to learn abstract,fragmented,and difficult-to-understand knowledge systems thoroughly,but also integrates the knowledge into the practice of the enterprise-level project development,helping students experience the value of knowledge in complex engineering projects and thus improving their ability to solve complex engineering problems while learning theoretical knowledge. 展开更多
关键词 Software engineering Course group Course training Comprehensive project cases School-enterprise cooperation
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A Hybrid Model for Improving Software Cost Estimation in Global Software Development
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作者 Mehmood Ahmed Noraini B.Ibrahim +4 位作者 Wasif Nisar Adeel Ahmed Muhammad Junaid Emmanuel Soriano Flores Divya Anand 《Computers, Materials & Continua》 SCIE EI 2024年第1期1399-1422,共24页
Accurate software cost estimation in Global Software Development(GSD)remains challenging due to reliance on historical data and expert judgments.Traditional models,such as the Constructive Cost Model(COCOMO II),rely h... Accurate software cost estimation in Global Software Development(GSD)remains challenging due to reliance on historical data and expert judgments.Traditional models,such as the Constructive Cost Model(COCOMO II),rely heavily on historical and accurate data.In addition,expert judgment is required to set many input parameters,which can introduce subjectivity and variability in the estimation process.Consequently,there is a need to improve the current GSD models to mitigate reliance on historical data,subjectivity in expert judgment,inadequate consideration of GSD-based cost drivers and limited integration of modern technologies with cost overruns.This study introduces a novel hybrid model that synergizes the COCOMO II with Artificial Neural Networks(ANN)to address these challenges.The proposed hybrid model integrates additional GSD-based cost drivers identified through a systematic literature review and further vetted by industry experts.This article compares the effectiveness of the proposedmodelwith state-of-the-artmachine learning-basedmodels for software cost estimation.Evaluating the NASA 93 dataset by adopting twenty-six GSD-based cost drivers reveals that our hybrid model achieves superior accuracy,outperforming existing state-of-the-artmodels.The findings indicate the potential of combining COCOMO II,ANN,and additional GSD-based cost drivers to transform cost estimation in GSD. 展开更多
关键词 Artificial neural networks COCOMO II cost drivers global software development linear regression software cost estimation
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A Neural-network-based Alternative Scheme to Include Nonhydrostatic Processes in an Atmospheric Dynamical Core
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作者 Yang XIA Bin WANG +13 位作者 Lijuan LI Li LIU Jianghao LI Li DONG Shiming XU Yiyuan LI Wenwen XIA Wenyu HUANG Juanjuan LIU Yong WANG Hongbo LIU Ye PU Yujun HE Kun XIA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1083-1099,I0002,I0003,共19页
Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostat... Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostatic solver in an atmospheric dynamical core.The NAS is designed to replace this solver,which can be incorporated into any hydrostatic models so that existing well-developed hydrostatic models can effectively serve for a longer time.Recent advances in machine learning(ML)provide a potential tool for capturing the main complicated nonlinear-nonhydrostatic relationship.In this study,an ML approach called a neural network(NN)was adopted to select leading input features and develop the NAS.The NNs were trained and evaluated with 12-day simulation results of dry baroclinic-wave tests by the Weather Research and Forecasting(WRF)model.The forward time difference of the nonhydrostatic tendency was used as the target variable,and the five selected features were the nonhydrostatic tendency at the last time step,and four hydrostatic variables at the current step including geopotential height,pressure in two different forms,and potential temperature,respectively.Finally,a practical NAS was developed with these features and trained layer by layer at a 20-km horizontal resolution,which can accurately reproduce the temporal variation and vertical distribution of the nonhydrostatic tendency.Corrected by the NN-based NAS,the improved hydrostatic solver at different horizontal resolutions can run stably for at least one month and effectively reduce most of the nonhydrostatic errors in terms of system bias,anomaly root-mean-square error,and the error of the wave spatial pattern,which proves the feasibility and superiority of this scheme. 展开更多
关键词 neural network nonhydrostatic alternative scheme atmospheric model dynamical core
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Orchid diversity and distribution pattern in karst forests in eastern Yunnan Province,China
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作者 Qiang Liu Xunfeng Wu +4 位作者 Haitao Xing Kuanbo Chi Wenhua Wang Liang Song Xiaoke Xing 《Forest Ecosystems》 SCIE CSCD 2023年第3期348-356,共9页
Global biodiversity loss and mass extinction of species have raised serious global concerns,especially in fragile ecosystems.Karst forest,a well-known fragile ecosystem,is served as a natural laboratory for biogeograp... Global biodiversity loss and mass extinction of species have raised serious global concerns,especially in fragile ecosystems.Karst forest,a well-known fragile ecosystem,is served as a natural laboratory for biogeographical,ecological,evolutionary,and taxonomic research.However,species richness and distribution patterns in karst forests largely remain unclear.Orchidaceae has been regarded as the“flagship”group of plant diversity.In this study,we use Wanfengshan Nature Reserve in southeast Yunnan,China,as a model to determine the conservation status of orchids in the karst forest by conducting systematic field surveys in the past three years from 2019 to 2022.In total,we identified 78 orchid species in 35 genera in Wanfengshan Nature Reserve.The dominant species were Bulbophyllum andersonii,Eria coronaria,Nervilia mackinnonii and Paphiopedilum micranthum.Multiple life forms were also observed,including epiphyte(14.29%),facultative epiphyte(18.18%),lithophyte(23.38%),and terrestrial(44.15%).Orchid species richness showed a bimodal pattern varied with altitude,the higher richness was recorded at 1,500-1,600 and 1,200-1,300 m,while the minimum was below 1,100 m.Each independent hill is rich in orchid species including‘endemic’species.A total of 25(33.8%)orchid species were considered threatened by the Redlist of Chinese Vascular Plants(Qin et al.,2017),including 3 CR species,5 EN species and 17 VU species.We call for more research addressing the mechanisms of ecological adaption,mycorrhizal interactions,and pollination of orchids in karst forests,and effective ways for recovery and conservation of orchids. 展开更多
关键词 Orchid diversity Limestone forest Resource investigation Threatened status Orchid conservation
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Framework for Mainstreaming Climate Change into African Blue Economy Strategies to Enhance Adaptation, Mitigation, and Resilience in Sustainable Development
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作者 Patrick Karani Pierre Failler Asmerom Mengisteab Gilau 《American Journal of Climate Change》 2023年第3期376-404,共29页
This article outlines a framework for mainstreaming climate change into African blue economy Strategies. We underscore that the proliferation of the blue economy in climate change has gained momentum, however, there r... This article outlines a framework for mainstreaming climate change into African blue economy Strategies. We underscore that the proliferation of the blue economy in climate change has gained momentum, however, there remains no standardized approach, mechanism or framework for mainstreaming and integrating climate change into blue economy. The economic pillars of economic development, social equity, and environmental management, conservation and sustainability are at the center of the blue economy frontier. The surrounding blue economy components have led to discrepancies in how the blue economy is mainstreamed, integrated, implemented and what is prioritized on agile basis. This article takes a continental overview of current approaches to regional and national levels of blue economy realignment. In doing so this article provides the continental, regional and national assessments of blue economy implementation approaches, through the development of a stepwise innovative process. Using the available literature, data and information from blue economy strategies and other publicly available online information, we analyzed each region and national blue economy strategies to assess the levels of blue economy components mainstreamed into climate change. Throughout this article we outline the methodological approach we took in order to develop a stepwise process innovation for mainstreaming climate change into blue economy at national and regional levels This approach will allow for ongoing and continued mainstreaming and integrating of climate change into blue economy realignment, operationalization and implementation as the concept of blue economy continues to evolve. The approach entails a collective action process for an informed decision making to direct, guide and inform actions for climate change that will effectively and efficiently enhance adaptation, mitigation and resiliency anchored to sustainable development. It establishes linkages to blue economy strategies through an integrated approach. The article addresses the question “How does mainstreaming climate change into African blue economy strategies contribute to achieving sustainable development?” The methodology is based on desk-top study and literature review. This explores the process of mainstreaming, drawing on the countries and regional blue economy strategies, that have made progress in development of blue economy strategies, plans, guidelines and frameworks for governance coordination mechanism. In conclusion, the article states that mainstreaming climate change in Africa reflects a complex pathway of processes and stakeholders that need to be taken into consideration in further research, with particular focus on institutional policy change, administrative structures and transformation. 展开更多
关键词 Climate Change Blue Economy ADAPTATION MITIGATION Resiliency
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粉末冶金-热挤压制备超高强度Al-Zn-Mg-Cu合金的组织及力学性能 被引量:8
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作者 陈存广 韩未豪 +5 位作者 祁妙 董诗鹏 李沛 杨芳 郝俊杰 郭志猛 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第4期1195-1205,共11页
本文采用粉末冶金联合热挤压工艺制备了一种新型超高强度Al-10Zn-3.5Mg-1.5Cu合金,并对其组织演变和力学性能进行了研究。结果表明:烧结样品的晶粒尺寸与球磨粉末颗粒的尺寸相一致。烧结和热挤压样品的相对密度分别达到99.1%和100%。通... 本文采用粉末冶金联合热挤压工艺制备了一种新型超高强度Al-10Zn-3.5Mg-1.5Cu合金,并对其组织演变和力学性能进行了研究。结果表明:烧结样品的晶粒尺寸与球磨粉末颗粒的尺寸相一致。烧结和热挤压样品的相对密度分别达到99.1%和100%。通过晶粒细化、时效强化和弥散强化的综合作用机制,Al-10Zn-3.5Mg-1.5Cu合金经热挤压和热处理后,极限抗拉强度达到810 MPa,屈服强度达到770 MPa,断后伸长率达到8%。 展开更多
关键词 粉末冶金 AL-ZN-MG-CU合金 超高强度 热挤压
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Influence of the Feed Gas Composition on the Fischer-Tropsch Synthesis in Commercial Operations 被引量:3
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作者 Theo Lee 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第4期329-341,共13页
Key technical challenges relating to the Fischer-Tropsch (F-T) synthesis applied in the commercialization of coal/gas-to-liquids (CTL/GTL) technologies have been reviewed. Based on the experiences accumulated from... Key technical challenges relating to the Fischer-Tropsch (F-T) synthesis applied in the commercialization of coal/gas-to-liquids (CTL/GTL) technologies have been reviewed. Based on the experiences accumulated from pilot plant, semi-work test and lab researches, the influences of the H2/CO ratio and the CO2 in the feed gas on the F-T process as well as on CTL/GTL complex in terms of product yields, energy efficiency and carbon utilization efficiency have been studied. Being contrary to the current design schemes for F-T process using the coal derived syngas and the iron-based cata lyst, it is suggested to feed the F-T synthesis unit with a syngas having a H2/CO ratio of 0.5 and then adjusting to 1.4 via the recycling process. As a result, the carbon efficiency of the whole plant could be reached to as high as 50%. For the issue of CO2 addition to the feed gas, it is proved that only a diluting role is played under the current commercial slurry phase F-T process. 展开更多
关键词 Fischer-Tropsch synthesis gas-to-liquids feed gas composition carbon efficiency
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粉末冶金AA2024合金搅拌摩擦焊的组织和力学性能 被引量:2
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作者 韩未豪 李沛 +6 位作者 刘楠 陈存广 董诗鹏 郭志猛 杨芳 隋延力 VOLINSKY Alex A 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第3期871-882,共12页
本文通过搅拌摩擦焊(FSW)成功实现了粉末冶金AA2024铝合金挤压板材的焊接,在航空航天、汽车工业领域具有重要应用前景。为了确定FSW的最佳加工参数,对FSW接头的微观结构、力学性能和断裂行为进行研究。结果表明,当搅拌速度为2000 r/min... 本文通过搅拌摩擦焊(FSW)成功实现了粉末冶金AA2024铝合金挤压板材的焊接,在航空航天、汽车工业领域具有重要应用前景。为了确定FSW的最佳加工参数,对FSW接头的微观结构、力学性能和断裂行为进行研究。结果表明,当搅拌速度为2000 r/min、焊接速度为100 mm/min时,获得最优焊接接头性能,其抗拉强度、屈服强度和伸长率分别为415 MPa(母材强度的85%)、282 MPa和9.5%。焊接接头的硬度从合金基体到热影响区逐渐降低。由于FSW过程中反复搅拌产生热量,样品发生过时效,导致热影响区附近的强度和硬度最低。搅拌区的平均晶粒尺寸(2.15μm)小于母材(4.43μm)和热影响区(5.03μm),并且热影响区晶粒具有<110>择优取向。 展开更多
关键词 高强度铝合金 粉末冶金 AA2024 搅拌摩擦焊 力学性能
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电解铜粉与雾化铜粉的烧结组织及性能 被引量:1
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作者 李沛 陈存广 +5 位作者 秦乾 陆天行 邵艳茹 杨芳 郝俊杰 郭志猛 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第7期1966-1977,共12页
本文采用电解法和水气联合雾化法制备出超细铜粉,通过冷等静压、氢气烧结获得全致密铜。细铜粉具有较高的烧结驱动力,促进烧结收缩和致密化。电解铜粉烧结样品的晶粒尺寸小于雾化铜粉,且容易形成孪晶,这是由于电解铜粉氧含量低,冷等静... 本文采用电解法和水气联合雾化法制备出超细铜粉,通过冷等静压、氢气烧结获得全致密铜。细铜粉具有较高的烧结驱动力,促进烧结收缩和致密化。电解铜粉烧结样品的晶粒尺寸小于雾化铜粉,且容易形成孪晶,这是由于电解铜粉氧含量低,冷等静压过程使粉末产生较高残余应力。在1000℃烧结温度下,电解铜粉和雾化铜粉烧结体的相对密度分别达到99.3%和97.4%,高于文献报道的粉末冶金铜零件。两种粉末制备的烧结铜的抗拉强度和屈服强度接近,但电解铜粉烧结样品的延伸率(60%)高于水气联合雾化铜粉的烧结样品(44%)。电解铜粉烧结样品的晶界中不含氧化亚铜,因此具有高的密度和低的氧含量,最终获得优异的性能。 展开更多
关键词 铜粉 电解 水气联合雾化 烧结组织 性能
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Quantitative micro-electrochemical study of duplex stainless steel 2205 in 3.5wt%NaCl solution 被引量:1
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作者 Shuangyu Cai Keke Lu +3 位作者 Xinnan Li Lei Wen Feifei Huang Ying Jin 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第11期2053-2063,共11页
Duplex stainless steels(DSSs)are suffering from various localized corrosion attacks such as pitting,selective dissolution,crevice corrosion during their service period.It is of great value to quantitatively analyze an... Duplex stainless steels(DSSs)are suffering from various localized corrosion attacks such as pitting,selective dissolution,crevice corrosion during their service period.It is of great value to quantitatively analyze and grasp the micro-electrochemical corrosion behavior and related mechanism for DSSs on the micrometer or even smaller scales.In this work,scanning Kelvin probe force microscopy(SKPFM)and energy dispersive spectroscopy(EDS)measurements were performed to reveal the difference between the austenite phase and ferrite phase in microregion of DSS 2205.Then traditional electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization(PDP)tests were employed for micro-electrochemical characterization of DSS 2205 with different proportion phases inϕ40 andϕ10μm micro holes.Both of them can only be utilized for qualitative or semi-quantitative micro-electrochemical characterization of DSS 2205.Coulostatic perturbation method was employed for quantitative micro-electrochemical characterization of DSS 2205.What is more,the applicable conditions of coulostatic perturbation were analyzed in depth by establishing a detailed electrochemical interface circuit.A series of microregion coulostatic perturbations for DSS 2205 with different proportion phases inϕ10μm micro holes showed that as the austenite proportion increases,the corresponding polarization resistance of microregion increases linearly. 展开更多
关键词 duplex stainless steel 2205 quantitative micro-electrochemical study electrochemical impedance spectroscopy coulostatic perturbation scanning Kelvin probe force microscopy
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Transdermal delivery of fluorescein isothiocyanate-dextrans using the combination of microneedles and low-frequency sonophoresis 被引量:1
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作者 Boonnada Pamornpathomkul Sureewan Duangjit +3 位作者 Suvida Laohapatarapant Theerasak Rojanarata Praneet Opanasopit Tanasait Ngawhirunpat 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2015年第5期415-424,共10页
This study aimed to evaluate the patient-friendly methods that are used in the delivery of hydrophilic macromolecules into deep skin layers,in particular,the combination of microneedles patch(MNs patch)and low-frequen... This study aimed to evaluate the patient-friendly methods that are used in the delivery of hydrophilic macromolecules into deep skin layers,in particular,the combination of microneedles patch(MNs patch)and low-frequency sonophoresis(SN).The hydrophilic macromolecule drug fluorescein isothiocyanate(FITC)-dextrans(FD-4:MW 4.4 kDa)was used as the model drug in our experimental design.In this study,excised porcine skin was used to investigate and optimize the key parameters that determine effective MNs-and SNfacilitated FD-4 delivery.In vitro skin permeation experiments revealed that the combination of MNs patch with SN had a superior enhancing effect of skin permeation for FD-4 compared to MNs alone,SN alone or untreated skin,respectively.The optimal parameters for the combination of MNs and SN included the following:10 N insertion force of MNs,4 W/cm^(2)SN intensity,6 mm radiation diameter of the SN probe,2 min application time,and the continuous mode duty cycle of SN.In addition,vertical sections of skin,clearly observed under a confocal microscope,confirmed that the combination of MNs and SN enhanced permeation of FD-4 into the deep skin layers.These studies suggest that the combination of MNs and SN techniques could have great potential in the delivery of hydrophilic macromolecules into deep skin. 展开更多
关键词 MICRONEEDLE SONOPHORESIS Fluorescein isothiocyanate-dextran Transdermal drug delivery
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Thermodynamic and thermoelectric properties of titanium oxycarbide with metal vacancy 被引量:1
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作者 Bao Zhang Jiusan Xiao +1 位作者 Shuqiang Jiao Hongmin Zhu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第4期787-795,共9页
Normal titanium oxycarbide exhibits an excellent electrical conductivity and a high carrier concentration of approximately 10^(21) cm^(-3);however,the low Seebeck coefficient limits the thermoelectric application.In t... Normal titanium oxycarbide exhibits an excellent electrical conductivity and a high carrier concentration of approximately 10^(21) cm^(-3);however,the low Seebeck coefficient limits the thermoelectric application.In this study,first-principle calculations demonstrate that the metal vacancy of titanium oxycarbide weakens the density of state passing through the valence band at the Fermi level,impairing the carrier concentration and enhancing carrier mobility.Thermodynamic analysis justifies the formation of titanium oxycarbide with metal vacancy through solid-state reaction.Transmission electron microscopic images demonstrate the segregation of metal vacancy based on the observation of the defect-rich and single-crystal face-centered cubic regions.Metal vacancy triggers the formation of vacancy-rich and single-crystal face-centered cubic regions.The aggregation of metal vacancy leads to the formation of the vacancy-rich region and other regions with a semi-coherent interface,suppressing the carrier concentration from 1.71×10^(21) to 4.5×10^(20) cm^(-3) and resulting in the Seebeck coefficient from -11μV/K of TiC_(0.5)O_(0.5) to -64μV/K at 1073 K.Meanwhile,vacancies accelerate electron migration from 1.65 to 4.22 cm^(-2)·V^(-1)·s^(-1),maintaining high conductivity.The figure of merit(ZT)increases more than five orders of magnitude via the introduction of metal vacancy,with the maximum figure of 2.11×10^(-2) at 1073 K.These results indicate the potential thermoelectric application of metal-oxycarbide materials through vacancy engineering. 展开更多
关键词 titanium oxycarbide metal vacancy THERMOELECTRIC first-principle calculation thermodynamics
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ICT-based agricultural advisory services and nitrogen management practices:A case study of wheat production in China 被引量:1
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作者 DING Ji-ping LI Jing-han +2 位作者 LIU Jia-huan ZHANG Wei-feng JIA Xiang-ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第6期1799-1811,共13页
Excessive use of nitrogen fertilizer in China and its adverse effects on agricultural production have been a national and global concern.In addition to massive public initiatives to promote sustainable farm practices,... Excessive use of nitrogen fertilizer in China and its adverse effects on agricultural production have been a national and global concern.In addition to massive public initiatives to promote sustainable farm practices,grass-rooted innovations are emerging in the niche,many of which take the forms of information and communication technologies(ICT)and digital services.This study examines the effects of ICT-based extension services provided by an entrepreneurial startup on adopting sustainable farming practices.We found no significant reduction in N-fertilizer use for wheat production.But the ICT-based services promoted farmers to adapt N-fertilizer use towards site-specific management.The business model of the entrepreneurial venture faces great challenges in becoming participatory and financially sustainable. 展开更多
关键词 venture capital innovations precision farming private-public partnerships nitrogen management
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Identity Dynamics and Conflict in Collaborative Processes: The Case of Participatory Management of Protected Areas in Benin 被引量:3
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作者 Latifou Idrissou Noelle Aarts +2 位作者 Cees Leeuwis Cees Leeuwis Annemarie Van Paassen 《Journal of Environmental Protection》 2016年第13期1981-2008,共29页
The research reported in this paper investigated the role of identity construction in the emergence and escalation of conflict in the participatory management of protected areas in Benin. The study shows that social i... The research reported in this paper investigated the role of identity construction in the emergence and escalation of conflict in the participatory management of protected areas in Benin. The study shows that social identity salience was dynamic and played an important role in the emergence and escalation of conflict in the studied cases. Conflicts emerged when identities became salient as a result of the stake-holders’ framing of contextual factors as a threat to their identity. The conflicts escalated when decisions and actions undertaken in the management process were framed as top-down and as posing a threat to the identities of the stakeholders. We conclude that, although the government in the management of the protected areas introduced participation, unilateral decisions taken about the way the conflicts should be managed caused disappointment and distrust, and thus led to a greater distance between the parties involved and to conflict escalation. 展开更多
关键词 PARTICIPATION Social Identity CONFLICT Protected Areas BENIN
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3D凝胶打印VC强化的高钒高速钢
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作者 陈存广 孙海霞 +3 位作者 杨芳 秦乾 何新波 郭志猛 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第4期1144-1154,共11页
VC强化的硬质材料,如高钒高速钢(HVHSS)因高的硬度和强度,不适合低成本加工成复杂形状。研究利用60%高固含量的打印浆料通过3D凝胶打印技术(3DGP)打印HVHSS零件。通过打印参数优化,打印试样的表面质量好,可观察到明显的打印线。挤出丝... VC强化的硬质材料,如高钒高速钢(HVHSS)因高的硬度和强度,不适合低成本加工成复杂形状。研究利用60%高固含量的打印浆料通过3D凝胶打印技术(3DGP)打印HVHSS零件。通过打印参数优化,打印试样的表面质量好,可观察到明显的打印线。挤出丝原位固化后,其强度足以维持设计的形状。烧结后,试样均匀收缩,收缩率为15%,相对密度达到99%,其表面粗糙度由6.5μm降低至3.8μm。烧结试样具有致密的显微组织和细的碳化物。此外,烧结试样具有优良的综合性能,硬度为HRC 60,抗弯强度为3000 MPa,冲击功为20~26 J。本文提出的方法可用于直接制备复杂形状的硬质材料,省去了后续加工。 展开更多
关键词 3D凝胶打印 复杂形状 流变性为 打印形貌 力学性能
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Design and development of optimal invasomes for transdermal drug delivery using computer program
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作者 Sureewan Duangjit Tassanan Nimcharoenwan +2 位作者 Nutcha Chomya Natthporn Locharoenrat Tanasait Ngawhirunpat 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第1期52-53,共2页
Capsaicin(CAP)is a major pungent component that has been widely studied in medical and pharmaceutical fields.CAP was used both orally and topically for pain relief.However,the extreme pungency and the water insolubili... Capsaicin(CAP)is a major pungent component that has been widely studied in medical and pharmaceutical fields.CAP was used both orally and topically for pain relief.However,the extreme pungency and the water insolubility of CAP lead to its restriction in the development of CAP as drug delivery system[1].Our previous study suggested that the computer software exhibited a beneficial role in the development of menthosomes for transdermal drug delivery[2].To confirm the reliability and reproducibility of simultaneous optimal formulations,the optimal ultraflexible liposomes(invasomes)estimated by the computer software(Design Expert?)were experimentally formulated and investigated. 展开更多
关键词 DESIGN EXPERT Invasomes Liposomes CAPSAICIN
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Classification and Selection of Prototyping Activities for Interaction Design
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作者 Stefano Filippi Daniela Barattin 《Intelligent Information Management》 2012年第4期147-156,共10页
Because of the evolution of markets and technologies, prototyping concerns should be kept updated almost day by day. Moreover, user centered design moves the focus towards interaction issues. Prototyping activities ma... Because of the evolution of markets and technologies, prototyping concerns should be kept updated almost day by day. Moreover, user centered design moves the focus towards interaction issues. Prototyping activities matching such characteristics are already available, but they are not so diffused in the industrial domain. This is due to many reasons;an important one is that a rigorous classification of them is missing, as well as an effective helping tool for the selection of the best activities, given the design context. The research described in this paper aims at defining a new classification of prototyping activities, as well as at developing a selection algorithm to choose the best ones in an automatic way. These goals are pursued by defining a set of characteristics that allow describing accurately the prototyping activities. The resulting classification is made by five classes, based on eighteen characteristics. This classification is exploited by the first release of an algorithm for the selection of the best activities, chosen in order to satisfy design situations described thanks to a different set of eleven indices. Five experiences in the field have been used up to now as a starting point for validating the research outcomes. 展开更多
关键词 PROTOTYPING ACTIVITIES Interaction Design VIRTUAL REALITY AUGMENTED REALITY
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THE SCIENCE AND TECHNOLOGY BACKYARD AS A LOCAL LEVEL INNOVATION INTERMEDIARY IN RURAL CHINA 被引量:1
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作者 Jinghan LI Cees LEEUWIS +1 位作者 Nico HEERINK Weifeng ZHANG 《Frontiers of Agricultural Science and Engineering》 2022年第4期558-576,共19页
Agricultural innovation can be described as a coevolutionary process of technological innovation,symbolic change,and social or institutional innovation,which relies on the interactions and collaboration between multip... Agricultural innovation can be described as a coevolutionary process of technological innovation,symbolic change,and social or institutional innovation,which relies on the interactions and collaboration between multiple stakeholders.This view emphasizes the significance of innovation intermediaries in supporting the coevolution process of innovation.Many studies have provided evidence on how innovation intermediaries play roles in supporting the coevolution innovation process at a broader innovation system level.However,little emphasis has been given to the role of innovation intermediaries in supporting the coevolution process of innovation at the community level in rural China.To address this research gap,this paper offers a case study of a novel type of innovation support intervention designed to promote technical change at the community level,the Science and Technology Backyard(STB).The paper focuses on the efforts of a specific STB in Wangzhuang village to promote innovation in tillage methods in wheat production.The aims was to examine the role of this newly emerging innovation support intervention in supporting the coevolution process of innovation at the community level,and compare the outcome of the coevolution process in the village with an STB to that in villages without an STB.Innovation journey analysis is applied to understand the evolved intermediation roles in the innovation process,and multivariate regression analysis is employed to assess the outcome of the coevolution process in villages with and without an STB.The findings suggest that the roles of STBs have evolved from knowledge brokers to systemic innovation intermediaries that facilitate the coevolution process of innovation inside an STB village.It has led to a higher adoption rate of improved technology,a better enabling environment for learning,and more effective institutional support in STB villages than in non-STB villages.However,the effect of support provided by a single STB on the coevolution process outside the community was limited.This finding points to a need for collaboration mechanisms and for connecting single STBs to support the coevolution process of innovation at a larger scale. 展开更多
关键词 agricultural innovation coevolution community level innovation intermediaries Science and Technology Backyards(STBs)
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Insight into relationship between composition,thickness and electrochemistry behavior of oxide film formed on TA15under different potentials in 0.5 mol·L^(-1)H_(2)SO_(4)
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作者 Fei-Fei Huang Yi Qin +4 位作者 Qing-Rui Wang Hiroaki Yoshida Lei Wen Hai Chang Ying Jin 《Rare Metals》 SCIE EI CAS CSCD 2023年第5期1760-1772,共13页
The oxide film formed on TA15 alloy in0.5 mol·L^(-1)H_(2)SO_(4)at different applied potentials is investigated by evaluating the film formation current density,film thickness,surface film composition,valence stat... The oxide film formed on TA15 alloy in0.5 mol·L^(-1)H_(2)SO_(4)at different applied potentials is investigated by evaluating the film formation current density,film thickness,surface film composition,valence state,and the electrochemical characteristics.The relative quantitative spectral analysis revealed by X-ray photoelectron spectroscopy(XPS)and X-ray absorption spectra(XAS)shows that the increasing applied potential promotes the formation of thick and high-valence state films.By contrasting with XAS of the reference titanium oxides,it is found that TiO_(2)within the oxide film changes from anatase type to rutile type with the potential increases to 2.00 V.The oxide film formed at passive region has better protection performance,and with the increase of applied potential,the corrosion resistance of passive film increases,whereas the ND(donor density)values obtained from the Mott-Schottky(MS)results decrease with the increasing applied potential,indicating a better uniformity and protective effect of the oxide film.Based on above facts,the model of the oxide films formed on TA15 at different applied potentials in passive region and dissolve region is proposed.Besides,the existence forms of all the TA15alloying elements under the most corrosion resistant condition are confirmed. 展开更多
关键词 TA15 Electrochemical passivation Corrosion behavior Surface compositions and structures
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Cuttlebone: Characterisation, Application and Development of Biomimetic Materials 被引量:4
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作者 Joseph Cadman Shiwei Zhou +1 位作者 Yuhang Chen Qing Li 《Journal of Bionic Engineering》 SCIE EI CSCD 2012年第3期367-376,共10页
Cuttlebone signifies a special class of ultra-lightweight cellular natural material possessing unique chemical, mechanical and structural properties, which have drawn considerable attention in the literature. The aim ... Cuttlebone signifies a special class of ultra-lightweight cellular natural material possessing unique chemical, mechanical and structural properties, which have drawn considerable attention in the literature. The aim of this paper is to better understand the mechanical and biological roles of cuttlebone. First, the existing literature concerning the characterisation and potential applications inspired by this remarkable biomaterial is critiqued. Second, the finite element-based homogenisation method is used to verify that morphological variations within individual cuttlebone samples have minimal impact on the effective me- chanical properties. This finding agrees with existing literature, which suggests that cuttlebone strength is dictated by the cut- tlefish habitation depth. Subsequently, this homogenisation approach is further developed to characterise the effective me- chanical bulk modulus and biofluidic permeability that cuttlebone provides, thereby quanti lying its mechanical and transporting functionalities to inspire bionic design of structures and materials for more extensive applications. Finally, a brief rationale for the need to design a biomimetic material inspired by the cuttlebone microstructure is provided, based on the preceding inves- tigation. 展开更多
关键词 CUTTLEBONE characterisation BIOMIMETIC HOMOGENISATION
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