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Flexible nest site selection of the endangered Oriental Storks(Ciconia boyciana):Trade-off from adaptive strategies 被引量:3
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作者 Lei Cheng Lizhi Zhou +2 位作者 Chao Yu Zhenhua Wei Chunhua Li 《Avian Research》 SCIE CSCD 2023年第2期242-249,共8页
Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selectio... Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications.In this study,we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks(Ciconia boyciana)in different nest areas.Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas,and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas.The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks.The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain;however,nest height decreased with the abundance of food resources in the Northeast China nest area.Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies.In safer environments,nests were lower and closer to food resources,which allows parent storks to invest more in the nestlings.However,in areas where human activity was intense,nests were higher to ensure the safety of their offspring.Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting.Finally,the establishment of soft barriers around the nesting areas could increase the safety of nests. 展开更多
关键词 adaptive strategies Breeding range expansion Habitat characteristics Nest site selection Oriental storks
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Sample size adaptive strategy for time-dependent Monte Carlo particle transport simulation 被引量:3
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作者 Dan-Hua ShangGuan Wei-Hua Yan +3 位作者 Jun-Xia Wei Zhi-Ming Gao Yi-Bing Chen Zhi-Cheng Ji 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第4期127-134,共8页
When multiphysics coupling calculations contain time-dependent Monte Carlo particle transport simulations, these simulations often account for the largest part of the calculation time, which is insufferable in certain... When multiphysics coupling calculations contain time-dependent Monte Carlo particle transport simulations, these simulations often account for the largest part of the calculation time, which is insufferable in certain important cases. This study proposes an adaptive strategy for automatically adjusting the sample size to fulfil more reasonable simulations. This is realized based on an extension of the Shannon entropy concept and is essentially different from the popular methods in timeindependent Monte Carlo particle transport simulations, such as controlling the sample size according to the relative error of a target tally or by experience. The results of the two models show that this strategy can yield almost similar results while significantly reducing the calculation time. Considering the efficiency, the sample size should not be increased blindly if the efficiency cannot be enhanced further. The strategy proposed herein satisfies this requirement. 展开更多
关键词 Time-dependent Monte Carlo particle transport simulation Shannon entropy adaptive strategy
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Unveiling the adaptation strategies of woody plants in remnant forest patches to spatiotemporal urban expansion through leaf trait networks
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作者 Mengping Jian Jingyi Yang 《Forest Ecosystems》 SCIE CSCD 2024年第2期247-254,共8页
Background:With the expansion of urban areas,the remnants of forested areas play a crucial role in preserving biodiversity in urban environments.This study aimed to explore the impact of spatiotemporal urban expansion... Background:With the expansion of urban areas,the remnants of forested areas play a crucial role in preserving biodiversity in urban environments.This study aimed to explore the impact of spatiotemporal urban expansion on the networks of leaf traits in woody plants within remnant forest patches,thereby enhancing our understanding of plant adaptive strategies and contributing to the conservation of urban biodiversity.Methods:Our study examined woody plants within 120 sample plots across 15 remnant forest patches in Guiyang,China.We constructed leaf trait networks (LTNs) based on 26 anatomical,structural,and compositional leaf traits and assessed the effects of the spatiotemporal dynamics of urban expansion on these LTNs.Results and conclusions:Our results indicate that shrubs within these patches have greater average path lengths and diameters than trees.With increasing urban expansion intensity,we observed a rise in the edge density of the LTN-shrubs.Additionally,modularity within the networks of shrubs decreased as road density and urban expansion intensity increased,and increases in the average path length and average clustering coefficient for shrubs were observed with a rise in the composite terrain complexity index.Notably,patches subjected to‘leapfrog’expansion exhibited greater average patch length and diameter than those experiencing edge growth.Stomatal traits were found to have high degree centrality within these networks,signifying their substantial contribution to multiple functions.In urban remnant forests,shrubs bolster their resilience to variable environmental pressures by augmenting the complexity of their leaf trait networks. 展开更多
关键词 Urban remnant forest patch Woody plant Leaf trait network Plant adaptation strategy Spatiotemporal urban expansion
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A systematic review of climate change impacts,adaptation strategies,and policy development in West Africa
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作者 Camillus Abawiera WONGNAA Alex Amoah SEYRAM Suresh BABU 《Regional Sustainability》 2024年第2期13-25,共13页
Climate change studies are diverse with no single study giving a comprehensive review of climate change impacts,adaptation strategies,and policy development in West Africa.The unavailability of an all-inclusive study ... Climate change studies are diverse with no single study giving a comprehensive review of climate change impacts,adaptation strategies,and policy development in West Africa.The unavailability of an all-inclusive study to serve as a guide for practitioners affects the effectiveness of climate change adaptation strategies proposed and adopted in the West African sub-region.The purpose of this study was to review the impacts of climate change risks on the crop,fishery,and livestock sectors,as well as the climate change adaptation strategies and climate-related policies aimed at helping to build resilient agricultural production systems in West Africa.The review process followed a series of rigorous stages until the final selection of 56 articles published from 2009 to 2023.Generally,the results highlighted the adverse effects of climate change risks on food security.We found a continuous decline in food crop production.Additionally,the livestock sector experienced morbidity and mortality,as well as reduction in meat and milk production.The fishery sector recorded loss of fingerlings,reduction in fish stocks,and destruction of mariculture and aquaculture.In West Africa,climate-smart agriculture technologies,physical protection of fishing,and inclusion of gender perspectives in programs appear to be the major adaptation strategies.The study therefore recommends the inclusion of ecosystem and biodiversity restoration,weather insurance,replacement of unsafe vessels,and strengthening gender equality in all climate change mitigation programs,as these will help to secure enough food for present and future generations. 展开更多
关键词 Climate change Climate extreme events Food security adaptation strategies Climate-smart AGRICULTURE West Africa
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Farmers’ Knowledge and Perceptions of the Effects of Climate Variability and Pollution on Crop Production and Their Varying Adaptation Strategies in The Gambia
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作者 Pierre Anthony Mendy Mawa Kone +7 位作者 Ado Baba Ahmed Sidat Yaffa Alpha Kargbo Afua Amponsah Amankwah Kossi-Messan Jacques Agboka Blessing Chinomso Okorie Assan Sowe Echene Jatta 《American Journal of Climate Change》 2024年第3期543-566,共24页
Crop and livestock production is critical to food security in The Gambia. Over the years, the country has experienced a reduced yield due to perceived climate change events with limited studies on how climate change a... Crop and livestock production is critical to food security in The Gambia. Over the years, the country has experienced a reduced yield due to perceived climate change events with limited studies on how climate change and pollution affect crop production. This study assesses farmers’ knowledge and perceptions of the effects of climate variability and pollution on crop production and their varying adaptation strategies in The Gambia. Both quantitative and qualitative methods were used in this study. The sample size for quantitative data collection was calculated as 432 while the qualitative data involves both the focus group discussions and key informant interviews. The focus group discussions comprised two districts in each of the six agricultural regions and two farming communities engaged in crop production were chosen from each district. Furthermore, eight key informant interviews from relevant institutions were conducted. The study shows that The Gambia is highly vulnerable to extreme climatic events. Although most farmers opined that agricultural land contamination emanates from farm runoff and indiscriminate waste dumping, they had little knowledge of heavy metal pollution and bioremediation. The results showed that farmers experienced constraints such as inadequate access to credit, water, and irrigation facilities, insufficient access to efficient inputs, salt intrusion, etc. which threatened food security. The study concludes that crop farmers acknowledged the existence and impacts of climate change, and therefore recommend the availability and affordability of climate change resilient crops and promote variability awareness campaigns to address climate change impacts in The Gambia. 展开更多
关键词 Climate Change Extreme Weather VULNERABILITY RISKS Hazards adaptation Strategies
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Transcriptomic and physiological analyses identifying Lanzhou lily(Lilium davidii var.unicolor)drought adaptation strategies 被引量:6
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作者 Wenmei Li Yajun Wang +4 位作者 Heng Ren Zhihong Guo Na Li Chengzheng Zhao Zhongkui Xie 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第1期145-157,共13页
Drought stress is the main limiting plant growth factor in arid and semiarid regions.The Lanzhou lily(Lilium davidii var.unicolor)is the only sweet-tasting lily grown in these regions of China that offers highly edibl... Drought stress is the main limiting plant growth factor in arid and semiarid regions.The Lanzhou lily(Lilium davidii var.unicolor)is the only sweet-tasting lily grown in these regions of China that offers highly edible,medicinal,health,and ornamental value.The Tresor lily is an ornamental flower known for its strong resistance.Plants were grown under three different drought intensity treatments,namely,being watered at intervals of 5,15,and 25 d(either throughout the study or during specific growth stages).We measured the biomass,leaf area,photosynthetic response,chlorophyll content(SPAD value),and osmoregulation of both the Lanzhou lily and the Tresor lily(Lilium‘Tresor’).Additionally,we employed RNA sequencing(RNA-Seq)and qRT-PCR to investigate transcriptomic changes of the Lanzhou lily in response to drought stress.Results showed that under drought stress,the decreasing rate in the Lanzhou lily bulb weight was lower than the corresponding Tresor lily bulb rate;the net photosynthetic rate,transpiration rate,and stomatal conductance of the Lanzhou lily were all higher compared to the Tresor lily;osmoregulation constituents,such as glucose,fructose,sucrose,trehalose,and soluble sugar,in the Lanzhou lily were comparatively higher;PYL,NCED,and ERS genes were significantly expressed in the Lanzhou lily.Under moderate drought,the biosynthesis of flavonoids,circadian rhythms,and the tryptophan metabolism pathway of the Lanzhou lily were all significant.Under severe drought stress,fatty acid elongation,photosynthetic antenna protein,plant hormone signal transduction,flavone and flavonol biosynthesis,and the carotenoid biosynthesis pathway were all significant.The Lanzhou lily adapted to drought stress by coordinating its organs and the unique role of its bulb,regulating photosynthesis,increasing osmolyte content,activating circadian rhythms,signal transduction,fatty acid elongation metabolism,and phenylalanine and flavonoid metabolic pathways,which may collectively be the main adaptation strategy and mechanisms used by the Lanzhou lily under drought stress. 展开更多
关键词 Drought stress adaptation strategy OSMOLYTES Lanzhou lily Physiological characterization Transcription profiles
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Application of a Parallel Adaptive Cuckoo Search Algorithm in the Rectangle Layout Problem 被引量:1
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作者 Weimin Zheng Mingchao Si +2 位作者 Xiao Sui Shuchuan Chu Jengshyang Pan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2173-2196,共24页
The meta-heuristic algorithm is a global probabilistic search algorithm for the iterative solution.It has good performance in global optimization fields such as maximization.In this paper,a new adaptive parameter stra... The meta-heuristic algorithm is a global probabilistic search algorithm for the iterative solution.It has good performance in global optimization fields such as maximization.In this paper,a new adaptive parameter strategy and a parallel communication strategy are proposed to further improve the Cuckoo Search(CS)algorithm.This strategy greatly improves the convergence speed and accuracy of the algorithm and strengthens the algorithm’s ability to jump out of the local optimal.This paper compares the optimization performance of Parallel Adaptive Cuckoo Search(PACS)with CS,Parallel Cuckoo Search(PCS),Particle Swarm Optimization(PSO),Sine Cosine Algorithm(SCA),Grey Wolf Optimizer(GWO),Whale Optimization Algorithm(WOA),Differential Evolution(DE)and Artificial Bee Colony(ABC)algorithms by using the CEC-2013 test function.The results show that PACS algorithmoutperforms other algorithms in 20 of 28 test functions.Due to the superior performance of PACS algorithm,this paper uses it to solve the problem of the rectangular layout.Experimental results show that this scheme has a significant effect,and the material utilization rate is improved from89.5%to 97.8%after optimization. 展开更多
关键词 Rectangular layout cuckoo search algorithm parallel communication strategy adaptive parameter
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Climate change and Chinese farmers: Perceptions and determinants of adaptive strategies 被引量:10
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作者 ZHAI Shi-yan SONG Gen-xin +2 位作者 QIN Yao-chen YE Xin-yue Mark Leipnik 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第4期949-963,共15页
Farmers’ perceptions, beliefs, adaptive strategies, and barriers regarding climate change are critical to promoting sustainable ecosystems and societal stability. This paper is based on an extensive survey of 1 500 f... Farmers’ perceptions, beliefs, adaptive strategies, and barriers regarding climate change are critical to promoting sustainable ecosystems and societal stability. This paper is based on an extensive survey of 1 500 farmers and their households in Henan Province in China during 2013–2014. Henan is the largest agricultural province in China with over 51 million farmers. The survey results showed that approximately 57% of the respondents perceived the direct impact of climate change during the past 10 years, with 70.3% believing that climate change posed a risk to their livelihood. Not surprisingly, most farmers reported that they have adopted new measures to mitigate the negative impacts of climate change. The main barriers hindering farmers’ adopting adaptation measures were lack of funds and timely information. A multinomial logit model revealed that land ownership, knowledge of crop variety and the causes of climate change, as well as the belief of climate change, were all positively related to the likelihood of employing adaptive strategies. Moreover, the percentage of households engaging in agriculture activity, and years of engaging in farming were both negatively correlated with famer’s likelihood of adopting adaptation strategies. More importantly, farmers with high incomes were less likely to adopt adaptive strategies and more willing to engage in other business activities. In conclusion, it is important to communicate climate change related information and government policies in rural areas, promote farmer associations and other educational outreach efforts to assist Chinese farmers to deal with climate change. 展开更多
关键词 climate change Chinese farmers adaptive strategies Henan Province
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Climate Change vs Cultural Heritage: An Adaptation Strategy for the Archaeological Site of Ancient Messene
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作者 Vasiliki Pougkakioti Miltiades Lazoglou Eleni Maistrou 《American Journal of Climate Change》 2023年第3期456-488,共33页
This article examines the effects of climate change on archaeological sites, using as a case study the archaeological site of Ancient Messene in Greece, and proposes an integrated adaptation strategy. In order to dete... This article examines the effects of climate change on archaeological sites, using as a case study the archaeological site of Ancient Messene in Greece, and proposes an integrated adaptation strategy. In order to determine the site’s most significant risks, a climate data analysis was conducted, taking into account three different climate emission scenarios (Representative Concentration Pathways) and two future periods (2031-2060, 2071-2100). The Intergovernmental Panel on Climate Change (IPCC) vulnerability assessment methodology was adopted to assess the vulnerability of the archaeological site to the effects of climate change. This is the first time such a methodology has been followed in Greece. The analysis revealed that the site’s critical hazards are fire, desertification, and flooding. The geographical location of the site in an intensely dry microclimate and the lack of safe and functional electromechanical and road infrastructure increase its vulnerability. The materials of the monuments are indirectly and directly impacted by climate change, whereas the vegetation is negatively impacted by the frequency of extreme events, especially wildfires. Based on the analysis results, a five-axis adaptation strategy was developed. 展开更多
关键词 Climate Change Cultural Heritage Archaeological Site VULNERABILITY RESILIENCE adaptive Capacity adaptation strategy
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Climate Change, Adaptive Strategies and Rural Livelihoods in Semiarid Tanzania 被引量:3
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作者 Richard Y. M. Kangalawe James G. Lyimo 《Natural Resources》 2013年第3期266-278,共13页
Climate change is a global challenge to both sustainable livelihoods and economic development. In Tanzania as in most African countries, farming depends almost entirely on rainfall, a situation that makes agriculture ... Climate change is a global challenge to both sustainable livelihoods and economic development. In Tanzania as in most African countries, farming depends almost entirely on rainfall, a situation that makes agriculture and thus rural livelihoods especially in semiarid environments particularly vulnerable to climate change. This study analyses the impacts of climate change and variability on rural livelihoods with particular focus on agricultural production, food security and adaptive capacities in semiarid areas of Tanzania. The methods used in this study included focus group discussions, key informant interviews, household surveys and field observations. Results from the study indicate that communities understood climate change in terms of variability in rainfall patterns and amount, temperature patterns, wind, water availability, increased incidences of drought and decreased agricultural productivity. Communities in the study area acknowledged that while rainfall amounts have decreased over the last thirty years, temperatures have increased;an experience is also supported by meteorological data. Such changes were claimed to have reduced agricultural productivity particularly due to prolonged drought, inadequate and uneven distribution of rainfall as well as unpredictable onset and ending of rains. Stressors such as crop diseases and pests, low soil fertility and inadequate extension services were also reported to contribute to the decline in agricultural productivity and re-occurrence of food insecurity. In response, communities have developed multiple adaptation strategies, including growing of drought tolerant and early maturing crop varieties, increasing wetlands cultivation, water harvesting for small-scale irrigation and livestock keeping. However, households with limited livelihood assets are more vulnerable to the impacts of climate change and food insecurity. The study argues that diversification of adaptive strategies, such as water harvesting for small-scale irrigation, integration of livestock and crop production are crucial to ensuring sustainable livelihood in a changing climate. 展开更多
关键词 CLIMATE Change adaptive Strategies FOOD INSECURITY RURAL Livelihoods SEMIARID Tanzania
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MEC-Assisted Flexible Transcoding Strategy for Adaptive Bitrate Video Streaming in Small Cell Networks 被引量:2
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作者 Chunyu Liu Heli Zhang +1 位作者 Hong Ji Xi Li 《China Communications》 SCIE CSCD 2021年第2期200-214,共15页
Adaptive bitrate video streaming(ABR)has become a critical technique for mobile video streaming to cope with time-varying network conditions and different user preferences.However,there are still many problems in achi... Adaptive bitrate video streaming(ABR)has become a critical technique for mobile video streaming to cope with time-varying network conditions and different user preferences.However,there are still many problems in achieving high-quality ABR video streaming over cellular networks.Mobile Edge Computing(MEC)is a promising paradigm to overcome the above problems by providing video transcoding capability and caching the ABR video streaming within the radio access network(RAN).In this paper,we propose a flexible transcoding strategy to provide viewers with low-latency video streaming services in the MEC networks under the limited storage,computing,and spectrum resources.According to the information collected from users,the MEC server acts as a controlling component to adjust the transcoding strategy flexibly based on optimizing the video caching placement strategy.Specifically,we cache the proper bitrate version of the video segments at the edge servers and select the appropriate bitrate version of the video segments to perform transcoding under jointly considering access control,resource allocation,and user preferences.We formulate this problem as a nonconvex optimization and mixed combinatorial problem.Moreover,the simulation results indicate that our proposed algorithm can ensure a low-latency viewing experience for users. 展开更多
关键词 mobile edge computing adaptive bi-trate video streaming flexible transcoding strategy ADMM
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Climate Change Perceptions , Impacts and Adaptation Strategies of F arm Households in Potohar Region of Punjab, Pakistan
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作者 Sohaib Aqib Syed Mohsin Ali Kazmi +2 位作者 Muhammad Amjad Ahmed Ali Soomro Ghulam Farooque Khoso 《Journal of Energy and Power Engineering》 CAS 2023年第4期136-151,共16页
Climate change has become a global phenomenon and is adversely affecting agricultural development across the globe.Developing countries like Pakistan where 18.9%of the GDP(gross domestic product)came from the agricult... Climate change has become a global phenomenon and is adversely affecting agricultural development across the globe.Developing countries like Pakistan where 18.9%of the GDP(gross domestic product)came from the agriculture sector and also 42%of the labor force involved in agriculture.They are directly and indirectly affected by climate change due to an increase in the frequency and intensity of climatic extreme events such as floods,droughts and extreme weather events.In this paper,we have focused on the impact of climate change on farm households and their adaptation strategies to cope up the climatic extremes.For this purpose,we have selected farm households by using multistage stratified random sampling from four districts of the Potohar region i.e.Attock,Rawalpindi,Jhelum and Chakwal.These districts were selected by dividing the Potohar region into rain-fed areas.We have employed logistic regression to assess the determinants of adaptation to climate change and its impact.We have also calculated the marginal effect of each independent variable of the logistic regression to measure the immediate rate of change in the model.In order to check the significance of our suggested model,we have used hypothesis testing. 展开更多
关键词 Climate change multistage stratified random sampling IMPACTS adaptation strategies logistic regression marginal effect Hypothesis testing
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Farmer's Adaptive Strategies on Land Competition between Societal Outcomes and Agroecosystem Conservation in the Purple-soiled Hilly Region,Southwestern China 被引量:3
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作者 TANG Qiang BAO Yuhai +2 位作者 HE Xiubin ZHU Bo ZHANG Xinbao 《Journal of Mountain Science》 SCIE CSCD 2012年第1期77-86,共10页
The worldwide extension and intensification of farming during the last century has led to ecosystem degradation and caused a series of environmental problems.Conservation of ecosystem services in agricultural regions ... The worldwide extension and intensification of farming during the last century has led to ecosystem degradation and caused a series of environmental problems.Conservation of ecosystem services in agricultural regions has been implemented by top-down government actions or initiated by resilience scientists in the developed countries,but little attention was paid in the developing countries,especially in some remote mountainous regions.The present paper presents a case study showing how local farmers obtained both maximal societal outcomes and agroecosystem conservation interests in the absence of distinct boundaries between agricultural and protected ecological areas in the densely populated purple-soiled hilly region of southwestern China.The local community(Yanting County) has developed a mosaic agricultural-forestry-fishery-stock breeding system with spatially targeted land uses,diverse agricultural productions and multiple ecological partnerships.It indicates that the local farmers have hereditarily perceived sound strategies on maximizing sustainable societal outcomes and optimizing tradeoffs among macro-market,state policy,new technological facility and ecological reinforcement. 展开更多
关键词 Mosaic agroforestry system adaptive strategies Land competition Agroecosystem conservation Purple-soiled hilly region China
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A Study on German Translation Strategies of Culture-Loaded Words in Documentary Hexi Corridor(Expert)by Adaptation Theory
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作者 ZHU Yalin NI Xiaoshan 《Sino-US English Teaching》 2023年第2期74-79,共6页
This paper deals with the translation strategies of Chinese Culture-Loaded Words from the perspective of adaptation theory.It is based on the translation text of the sixth episode“Silk Road”and the seventh episode“... This paper deals with the translation strategies of Chinese Culture-Loaded Words from the perspective of adaptation theory.It is based on the translation text of the sixth episode“Silk Road”and the seventh episode“Dunhuang”of the documentary Hexi Corridor.Many words with Chinese cultural connotations appear in the subtitles of this documentary.This paper will be divided into four parts.The first part and the second part deal with the basic theories,i.e.,definition of Chinese Culture-Loaded Words and of adaptation theory.The original text is analysed in the third part.This part deals with the background and specifics of the language of the documentary film Hexi Corridor.The fourth part deals with the difficulties encountered by the author in translation practice and the corresponding solutions adopted by the author.The translation difficulties are solved by five translation methods,namely transliteration,loan translation,substitution,interpretation,and adaptation. 展开更多
关键词 Chinese Culture-Loaded Words adaptation theory documentary film Hexi Corridor translation strategies and methods
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Research on the Control Strategy of Micro Wind-Hydrogen Coupled System Based on Wind Power Prediction and Hydrogen Storage System Charging/Discharging Regulation
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作者 Yuanjun Dai Haonan Li Baohua Li 《Energy Engineering》 EI 2024年第6期1607-1636,共30页
This paper addresses the micro wind-hydrogen coupled system,aiming to improve the power tracking capability of micro wind farms,the regulation capability of hydrogen storage systems,and to mitigate the volatility of w... This paper addresses the micro wind-hydrogen coupled system,aiming to improve the power tracking capability of micro wind farms,the regulation capability of hydrogen storage systems,and to mitigate the volatility of wind power generation.A predictive control strategy for the micro wind-hydrogen coupled system is proposed based on the ultra-short-term wind power prediction,the hydrogen storage state division interval,and the daily scheduled output of wind power generation.The control strategy maximizes the power tracking capability,the regulation capability of the hydrogen storage system,and the fluctuation of the joint output of the wind-hydrogen coupled system as the objective functions,and adaptively optimizes the control coefficients of the hydrogen storage interval and the output parameters of the system by the combined sigmoid function and particle swarm algorithm(sigmoid-PSO).Compared with the real-time control strategy,the proposed predictive control strategy can significantly improve the output tracking capability of the wind-hydrogen coupling system,minimize the gap between the actual output and the predicted output,significantly enhance the regulation capability of the hydrogen storage system,and mitigate the power output fluctuation of the wind-hydrogen integrated system,which has a broad practical application prospect. 展开更多
关键词 Micro wind-hydrogen coupling system ultra-short-term wind power prediction sigmoid-PSO algorithm adaptive roll optimization predictive control strategy
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Effect of Socio-Demographic Characteristics on Kenyan Smallholder Dairy Farmers’ Adaptive Strategies to Climate Change Effects
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作者 Charles Okech Odhiambo Chlirukovian Bwire Wasike Harun Okello Ogindo 《Atmospheric and Climate Sciences》 2019年第4期583-599,共17页
Climate change (CC) impedes smallholder dairy industry in Kenya. Consequently, farmers’ adaptation to CC effects would greatly determine their resilience, profitability, and sustainable contribution to the economy. S... Climate change (CC) impedes smallholder dairy industry in Kenya. Consequently, farmers’ adaptation to CC effects would greatly determine their resilience, profitability, and sustainable contribution to the economy. Socio-demography among other factors, determine smallholder farmers’ adaptive strategies to CC effects. This study sought to understand how smallholder dairy farmers in South Western Kenya adapt to climate changes and determine the relationship between famers’ adaptive strategies and their socio-demographics of sex, age, marital status, highest educational level, household size, and experience in dairying. Concurrent Fixed Mixed Methods were used to collect primary and secondary data. Reports and papers were reviewed for temperature and precipitation data, dairy population, production trends, and farmers’ socio-demographics. A survey questionnaire was administered to 367 smallholder dairy household heads with 10 years’ experience obtained through multi-stage sampling of respondents from 4 sub counties of Migori county. The data collected included the respondents’ socio-demographics, climate changes and adaptability to CC effects. Key informant interviews (KIIs) were conducted with heads of government departments of Livestock Production, Cooperative Development, Meteorology, Environment and Agriculture Sector Development Support Programme (ASDSP) in Migori County. Others included the leadership of Rongo Dairy Farmers’ Cooperative Society, Lichota Livestock Development Farm, and a Research Officer for Livestock Production Systems with Kenya Agriculture and Livestock Research Organization (KALRO). Focus group discussions (FGDs), on the other hand, were conducted with old men and women (aged 60 years and above), and farmer groups from Rongo Dairy Farmers Cooperative Society, Cham Gi Wadu Dairy and Multipurpose Cooperative Society, and East Sakwa Farmers’ Development Group. These were obtained purposively based on dairying experience. Descriptive statistics (percentages) were used to describe climate change effect on smallholder dairying and farmers’ adaptation. Percentages, minimum and maximum values, means, range, and standard deviations were used to describe respondents’ socio-demographics. Binary logistic regression analysis was used to determine the effect of farmers’ socio-demographics on their adaptive strategies to CC effects. Results indicated that individually, male farmers were more likely to adopt mixed crop and livestock farming (Odds = 3.97;p = 0.02) and experience an increasing trend in income earning from milk sales (Odds = 0.63;p = 0.04). Individually, older farmers were significantly more likely to establish own fodder (Odds = 0.96;p = 0.03), keep non-Friesians and their crosses (Odds = 0.97;p = 0.02), and experience increasing trends in income earned from milk sales (odds = 1.02;p = 0.02). Individually, household size significantly influenced establishment of own fodder (Odds = 0.69;p = 0.00) and jointly with the other 5 socio-demographic factors (Odds = 0.70;p = 0.00). With other socio-demographic factors, male farmers were more likely to rely mainly on household labour (Odds = 0.32;p = 0.05). Thus, gender, age and household size were found to have significant effects on smallholder dairy farmers’ adaptation to climate change effects in the study area. 展开更多
关键词 SMALLHOLDER DAIRY FARMERS SOUTHWESTERN Kenya CLIMATE Change adaptation SOCIO-DEMOGRAPHIC Factors adaptive Strategies
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Adaptive Nonlinear Model Predictive Control Using an On-line Support Vector Regression Updating Strategy
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作者 王平 杨朝合 +1 位作者 田学民 黄德先 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期774-781,共8页
The performance of data-driven models relies heavily on the amount and quality of training samples, so it might deteriorate significantly in the regions where samples are scarce. The objective of this paper is to deve... The performance of data-driven models relies heavily on the amount and quality of training samples, so it might deteriorate significantly in the regions where samples are scarce. The objective of this paper is to develop an online SVR model updating strategy to track the change in the process characteristics efficiently with affordable computational burden. This is achieved by adding a new sample that violates the Karush–Kuhn–Tucker conditions of the existing SVR model and by deleting the old sample that has the maximum distance with respect to the newly added sample in feature space. The benefits offered by such an updating strategy are exploited to develop an adaptive model-based control scheme, where model updating and control task perform alternately.The effectiveness of the adaptive controller is demonstrated by simulation study on a continuous stirred tank reactor. The results reveal that the adaptive MPC scheme outperforms its non-adaptive counterpart for largemagnitude set point changes and variations in process parameters. 展开更多
关键词 adaptive control Support vector regression Updating strategy Model predictive control
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Multivariate adaptive regression splines based simulation optimization using move-limit strategy
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作者 毛虎平 吴义忠 陈立平 《Journal of Shanghai University(English Edition)》 CAS 2011年第6期542-547,共6页
This paper makes an approach to the approximate optimum in structural design,which combines the global response surface(GRS) based multivariate adaptive regression splines(MARS) with Move-Limit strategy(MLS).MAR... This paper makes an approach to the approximate optimum in structural design,which combines the global response surface(GRS) based multivariate adaptive regression splines(MARS) with Move-Limit strategy(MLS).MARS is an adaptive regression process,which fits in with the multidimensional problems.It adopts a modified recursive partitioning strategy to simplify high-dimensional problems into smaller highly accurate models.MLS for moving and resizing the search sub-regions is employed in the space of design variables.The quality of the approximation functions and the convergence history of the optimization process are reflected in MLS.The disadvantages of the conventional response surface method(RSM) have been avoided,specifically,highly nonlinear high-dimensional problems.The GRS/MARS with MLS is applied to a high-dimensional test function and an engineering problem to demonstrate its feasibility and convergence,and compared with quadratic response surface(QRS) models in terms of computational efficiency and accuracy. 展开更多
关键词 global response surface(GRS) multivariate adaptive regression splines(MARS) Move-Limit strategy(MLS) quadratic response surface(QRS)
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Variable Parameter Self-Adaptive Control Strategy Based on Driving Condition Identification for Plug-In Hybrid Electric Bus 被引量:1
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作者 Kongjian Qin Yu Liu Xi Hu 《Journal of Beijing Institute of Technology》 EI CAS 2019年第1期162-170,共9页
A variable parameter self-adaptive control strategy based on driving condition identification is proposed to take full advantage of the fuel saving potential of the plug-in hybrid electric bus(PHEB).Firstly,the princi... A variable parameter self-adaptive control strategy based on driving condition identification is proposed to take full advantage of the fuel saving potential of the plug-in hybrid electric bus(PHEB).Firstly,the principal component analysis(PCA)and the fuzzy c-means clustering(FCM)algorithm is used to construct the comprehensive driving cycle,congestion driving cycle,urban driving cycle and suburban driving cycle of Chinese urban buses.Secondly,an improved particle swarm optimization(IPSO)algorithm is proposed,and is used to optimize the control parameters of PHEB under different driving cycles,respectively.Then,the variable parameter self-adaptive control strategy based on driving condition identification is given.Finally,for an actual running vehicle,the driving condition is identified by relevance vector machine(RVM),and the corresponding control parameters are selected to control the vehicle.The simulation results show that the fuel consumption of using the variable parameter self-adaptive control strategy is reduced by 4.2% compared with that of the fixed parameter control strategy,and the feasibility of the variable parameter self-adaptive control strategy is verified. 展开更多
关键词 PLUG-IN hybrid electric bus(PHEB) variable PARAMETER SELF-adaptive control strategy energy CONSUMPTION
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On the E-Valuation of Certain E-Business Strategies on Firm Performance by Adaptive Algorithmic Modeling: An Alternative Strategic Managerial Approach
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作者 Alexandra Lipitakis Evangelia A.E.C. Lipitakis 《Computer Technology and Application》 2012年第1期38-46,共9页
This paper describes an innovative adaptive algorithmic modeling approach, for solving a wide class of e-business and strategic management problems under uncertainty conditions. The proposed methodology is based on ba... This paper describes an innovative adaptive algorithmic modeling approach, for solving a wide class of e-business and strategic management problems under uncertainty conditions. The proposed methodology is based on basic ideas and concepts of four key-field interrelated sciences, i.e., computing science, applied mathematics, management sciences and economic sciences. Furthermore, the fundamental scientific concepts of adaptability and uncertainty are shown to play a critical role of major importance for a (near) optimum solution of a class of complex e-business/services and strategic management problems. Two characteristic case studies, namely measuring e-business performance under certain environmental pressures and organizational constraints and describing the relationships between technology, innovation and firm performance, are considered as effective applications of the proposed adaptive algorithmic modeling approach. A theoretical time-dependent model for the evaluation of firm e-business performances is also proposed. 展开更多
关键词 adaptive algorithms algorithmic modeling e-business problems e-service strategy management methodologies hybrid algorithmic modeling strategy management (SM) methodologies time-dependent performance evaluation model.
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