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Optimization of Nesting Systems in Shipbuilding:A Review
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作者 Sari Wanda Rulita Gunawan Muzhoffar Dimas Angga Fakhri 《哈尔滨工程大学学报(英文版)》 2025年第1期152-175,共24页
This review article provides a comprehensive analysis of nesting optimization algorithms in the shipbuilding industry,emphasizing their role in improving material utilization,minimizing waste,and enhancing production ... This review article provides a comprehensive analysis of nesting optimization algorithms in the shipbuilding industry,emphasizing their role in improving material utilization,minimizing waste,and enhancing production efficiency.The shipbuilding process involves the complex cutting and arrangement of steel plates,making the optimization of these operations vital for cost-effectiveness and sustainability.Nesting algorithms are broadly classified into four categories:exact,heuristic,metaheuristic,and hybrid.Exact algorithms ensure optimal solutions but are computationally demanding.In contrast,heuristic algorithms deliver quicker results using practical rules,although they may not consistently achieve optimal outcomes.Metaheuristic algorithms combine multiple heuristics to effectively explore solution spaces,striking a balance between solution quality and computational efficiency.Hybrid algorithms integrate the strengths of different approaches to further enhance performance.This review systematically assesses these algorithms using criteria such as material dimensions,part geometry,component layout,and computational efficiency.The findings highlight the significant potential of advanced nesting techniques to improve material utilization,reduce production costs,and promote sustainable practices in shipbuilding.By adopting suitable nesting solutions,shipbuilders can achieve greater efficiency,optimized resource management,and superior overall performance.Future research directions should focus on integrating machine learning and real-time adaptability to further enhance nesting algorithms,paving the way for smarter,more sustainable manufacturing practices in the shipbuilding industry. 展开更多
关键词 Cutting plate nesting algorithms nesting optimization Shipbuilding efficiency Algorithmic optimization
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Erratum: Fermi Surface Nesting with Heavy Quasiparticlesin the Locally Noncentrosymmetric Superconductor CeRh2As2
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作者 Yi Wu Yongjun Zhang +15 位作者 Sailong Ju Yong Hu Yanen Huang Yanan Zhang Huali Zhang Hao Zheng Guowei Yang Evrard-Ouicem Eljaouhari Baopeng Song Nicholas CPlumb Frank Steglich Ming Shi Gertrud Zwicknagl Chao Cao Huiqiu Yuan Yang Liu 《Chinese Physics Letters》 2025年第4期188-188,共1页
In the acknowledgements,[1]the first acknowledged grant number(2022YFA140220)is incorrect and should be changed to 2022YFA1402200.
关键词 fermi surface nesting locally noncentrosymmetric superconductor cerh heavy quasiparticles
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Anthropogenic nesting materials and reproductive performance of Chinese Bulbuls(Pycnonotus sinensis)along the urbanization gradient in Hangzhou,China 被引量:1
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作者 Xingmin Chen Qin Zhang +3 位作者 Sisi Lan Qin Huang Shuihua Chen Yanping Wang 《Avian Research》 SCIE CSCD 2024年第4期431-437,共7页
Urbanization induced by human activities presents both challenges and adaptive opportunities for wildlife.One notable impact of urban sprawl is the vast amount of waste it produces,which has discernible effects on wil... Urbanization induced by human activities presents both challenges and adaptive opportunities for wildlife.One notable impact of urban sprawl is the vast amount of waste it produces,which has discernible effects on wildlife.Interestingly,an emerging trend has been observed that birds are incorporating anthropogenic materials into their nests.However,the relationship between anthropogenic nesting materials(ANMs)and the reproductive performance of urban birds is unclear.In this study,we investigated the relationship between the incorporation of ANMs into nests and the reproductive performance of Chinese Bulbuls(Pycnonotus sinensis)by monitoring and collecting data on 136 breeding nests in Hangzhou,China.We gathered data on seven reproductive traits of Chinese Bulbuls,including laying date,incubation period,nestling period,clutch size,egg volume,hatching success rate,and fledging success rate.We then calculated the urbanization synthetic index as a measure of the level of urbanization and examined its relationship with the proportion and weight of ANMs.Through examination of nest components,we observed significant increase in the proportion and weight of ANMs with the urbanization synthetic index.Notably,we found a higher hatching success rate of Chinese Bulbuls with an increasing proportion of ANMs.However,the inclusion of ANMs in nests was not correlated with other reproductive traits of Chinese Bulbuls.Overall,the use of ANMs by Chinese Bulbuls is consistent with the adaptive hypothesis and the availability hypothesis.Further studies should use controlled experiments to investigate the impact of ANMs on avian reproductive success. 展开更多
关键词 Adaptive hypothesis Anthropogenic nesting materials Availability hypothesis Hatching success Reproductive traits URBANIZATION
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Implementation of a Nesting Repair Technology for Transportation Pipeline Repair
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作者 Yijun Gao Yong Wang +2 位作者 Qing Na Jiawei Zhang Aixiang Wu 《Fluid Dynamics & Materials Processing》 EI 2024年第11期2443-2458,共16页
Filling methods in the mining industry can maximize the recovery of mineral resources and protect the underground and surface environments.In recent years,such methods have been widely used in metal mines where pipeli... Filling methods in the mining industry can maximize the recovery of mineral resources and protect the underground and surface environments.In recent years,such methods have been widely used in metal mines where pipeline transportation typically plays a decisive role in the safety and stability of the entirefilling system.Because thefilling slurry contains a large percentage of solid coarse particles,the involved pipeline is typically eroded and often damaged during such a process.A possible solution is the so-called nesting repair technology.In the present study,nesting a 127 mm outer diameter pipeline in 151 mm inner diameter borehole is considered to meet the repair objective.First,by using the rheological theory,the pipeline transmission resistance and self-flow conveying range are calculated under different working conditions.It is shown that the pipeline transmission resistance is larger when the inner diameter of casing is 80 mm,and the limitflow rate of vertical pipeline self-flow is 120 m^(3)/h;moreover,when the pipeline diameter is 100 mm and theflow rate is 140 m^(3)/h,the self-flow conveying can be satisfied in most of the underground−455 m stage.Accordingly,a plan is presented for the nesting repair strategy,based on the installation of a drill bit under the casing and lowering the casing into the borehole as if it were a drill pipe.Finally,the outcomes of such a strategy are verified.Thefillingflow rate range using the new pipelines is found to be in the range from 188.60 to 224.39 m^(3)/h,and its averagefillingflow rate reaches 209.83 m^(3)/h when conveying 2319.6 m long-distance quarry. 展开更多
关键词 BOREHOLE nesting repair pipeline transmission resistance flow rate
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Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) prefer shells for nesting:A field experiment
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作者 Macarena Castro Andrés De la Cruz +1 位作者 Nuria Martin-Sanjuan Alejandro Pérez-Hurtado 《Avian Research》 SCIE CSCD 2024年第1期55-59,共5页
Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal wetlands.However,supratidal habitats as saltpans could play a role in buffering human impact.Saltpans have shown to be... Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal wetlands.However,supratidal habitats as saltpans could play a role in buffering human impact.Saltpans have shown to be important as feeding or breeding sites of some shorebird species.A potential conservation strategy to increase shorebird populations in saltpans is to manipulate the cues that birds use to select optimal breeding habitat.Here it is hypothesized that shorebirds are attracted to bivalve shells due to the advantages they offer.Following this hypothesis,we supplemented a restored saltpan in 2019 and 2021 with bivalve shells,expecting an increase in the number of breeding birds’ nests.More than 75% of Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) nests were found in patches with shells in both years.The best model for both species indicates that the presence of shells is the factor that most correlates with the location of nests.The probability of choosing one place over another to settle their nest increases in areas with an abundance of shells,double in the case of the Kentish Plover and triple in the case of the Little Tern.The result of this study may constitute a valuable tool for attracting birds to restored saltpans and could contribute to the success of expensive restoration projects where time is usually a constraint. 展开更多
关键词 Habitat management Nest site selection Saltpan restoration Shell supplementation SHOREBIRDS
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一种基于NeSTiNg的TSN强实时流量调度和自动配置方法 被引量:2
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作者 王波 高文炜 +1 位作者 徐丹妮 贺新乐 《微电子学与计算机》 2022年第11期62-68,共7页
流量调度是时间敏感网络(Time Sensitive Networking, TSN)技术的核心.在大型工业嵌入式系统应用中,TSN流量调度的设计和仿真阶段需要对链路、流、门控等调度信息进行复杂且苛刻的配置.现有的基于仿真框架的配置方法多采用手动配置,这... 流量调度是时间敏感网络(Time Sensitive Networking, TSN)技术的核心.在大型工业嵌入式系统应用中,TSN流量调度的设计和仿真阶段需要对链路、流、门控等调度信息进行复杂且苛刻的配置.现有的基于仿真框架的配置方法多采用手动配置,这阻碍了这些框架对大型TSN网络的适用性.基于TSN强实时流量传输机制和NeSTiNg(Network Simulator for Time-Sensitive Networking)框架,提出一种适用于大型网络的强实时流量调度和自动配置方法.首先,该方法区别于传统的手动配置输入方式,实现了对流偏移、门状态和路由表等信息的自动配置;其次,该方法提取了流的端到端时延,验证了大型网络中TSN传输的强实时性;最后,通过计算拓扑变化后选择新路径的运算时间,评估了该方法对动态拓扑的适用性.结果表明:该方法保证了大型网络中大量流传输的强实时性,且当拓扑改变时,相比于静态路由有更低的运算时间. 展开更多
关键词 TSN IEEE 802.1Qbv nesting 流量调度 自动配置 TSN评估 运算时间
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Algorithm for 2D irregular-shaped nesting problem based on the NFP algorithm and lowest-gravity-center principle 被引量:5
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作者 LIU Hu-yao HE Yuan-jun 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第4期570-576,共7页
The nesting problem involves arranging pieces on a plate to maximize use of material. A new scheme for 2D ir- regular-shaped nesting problem is proposed. The new scheme is based on the NFP (No Fit Polygon) algorithm a... The nesting problem involves arranging pieces on a plate to maximize use of material. A new scheme for 2D ir- regular-shaped nesting problem is proposed. The new scheme is based on the NFP (No Fit Polygon) algorithm and a new placement principle for pieces. The novel placement principle is to place a piece to the position with lowest gravity center based on NFP. In addition, genetic algorithm (GA) is adopted to find an efficient nesting sequence. The proposed scheme can deal with pieces with arbitrary rotation and containing region with holes, and achieves competitive results in experiment on benchmark datasets. 展开更多
关键词 nesting Cutting stock No Fit Polygon (NFP) Genetic algorithm (GA) Lowest gravity center
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眼针对脑缺血再灌注损伤大鼠Nesting、GAP43蛋白表达影响 被引量:7
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作者 宓丹 潘冲 陈雪 《辽宁中医药大学学报》 CAS 2018年第10期119-122,共4页
目的:通过观察眼针治疗对脑缺血再灌注损伤大鼠大脑皮层巢蛋白(Nesting)、生长相关蛋白43(Growth associated protein 43,GAP43)蛋白表达的影响,探讨眼针治疗对脑缺血后神经再生作用。方法:SD大鼠随机分为空白组、假手术组、模型... 目的:通过观察眼针治疗对脑缺血再灌注损伤大鼠大脑皮层巢蛋白(Nesting)、生长相关蛋白43(Growth associated protein 43,GAP43)蛋白表达的影响,探讨眼针治疗对脑缺血后神经再生作用。方法:SD大鼠随机分为空白组、假手术组、模型组(3 h、24 h、72 h)、眼针组(3 h、24 h、72 h),每组6只。采用改良线栓法制备大脑中动脉缺血2 h再灌注损伤模型,眼针组给予眼针治疗方法,每12 h 1次,每次20 min。各组大鼠在治疗点结束后,对大鼠神经功能缺损进行评分,用Westblot法检测缺血侧大脑皮层Nesting、GAP43蛋白含量。结果:(1)眼针组24 h、72 h神经功能评分低于同时间点的模型组(P〈0.05)。(2)脑缺血后模型组Nesting蛋白表达升高并随着缺血时间延长持续升高,与空白组比较,P〈0.05;眼针组Nesting蛋白表达趋势与模型组相似,与模型组同时间点比较,眼针组Nesting蛋白表达升高更明显(P〈0.05)。(3)脑缺血后模型组GAP43蛋白表达升高并随着缺血时间延长持续升高,与空白组比差异明显(P〈0.05);眼针组GAP43蛋白表达趋势与模型组相似,与模型组同时间点比较,眼针组GAP43蛋白表达升高更明显(P〈0.05)。结论:眼针治疗可以促进脑缺血后Nesting、GAP43蛋白的表达,从而具有促进脑缺血后神经发生的作用。 展开更多
关键词 脑缺血 眼针 神经发生 nesting GAP43
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Heuristic algorithm based on the principle of minimum total potential energy(HAPE):a new algorithm for nesting problems 被引量:2
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作者 Xiao LIU Jia-wei YE 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2011年第11期860-872,共13页
We present a new algorithm for nesting problems.Many equally spaced points are set on a sheet,and a piece is moved to one of the points and rotated by an angle.Both the point and the rotation angle constitute the pack... We present a new algorithm for nesting problems.Many equally spaced points are set on a sheet,and a piece is moved to one of the points and rotated by an angle.Both the point and the rotation angle constitute the packing attitude of the piece.We propose a new algorithm named HAPE(Heuristic Algorithm based on the principle of minimum total Potential Energy) to find the optimal packing attitude at which the piece has the lowest center of gravity.In addition,a new technique for polygon overlap testing is proposed which avoids the time-consuming calculation of no-fit-polygon(NFP).The detailed implementation of HAPE is presented and two computational experiments are described.The first experiment is based on a real industrial problem and the second on 11 published benchmark problems.Using a hill-climbing(HC) search method,the proposed algorithm performs well in comparison with other published solutions. 展开更多
关键词 Packing Cutting nesting Irregular Heuristic algorithm Minimum total potential energy
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Modelling the nesting-habitat of threatened vulture species in the caucasus:An ecosystem approach to formalising environmental factors in species distribution models 被引量:2
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作者 Rustam Pshegusov Victoria Chadaeva 《Avian Research》 SCIE CSCD 2023年第4期572-585,共14页
Abiotic factors play an important role in species localisation,but biotic and anthropogenic predictors must also be considered in distribution modelling for models to be biologically meaningful.In this study,we formal... Abiotic factors play an important role in species localisation,but biotic and anthropogenic predictors must also be considered in distribution modelling for models to be biologically meaningful.In this study,we formalised the biotic predictors of nesting sites for four threatened Caucasian vultures by including species distribution models(wild ungulates,nesting tree species)as biotic layers in the vulture Maxent models.Maxent was applied in the R dismo package and the best set of the model parameters were defined in the R ENMeval package.Performance metrics were continuous Boyce index,Akaike's information criterion,the area under receiver operating curve and true skill statistics.We also calculated and evaluated the null models.Kernel density estimation method was applied to assess the overlap of vulture ecological niches in the environmental space.The accessibility of anthropogenic food resources was estimated using the Path Distance measure that considers elevation gradient.The availability of pine forests(Scots Pine)and wild ungulates(Alpine Chamois and Caucasian Goat)contributed the most(29.6%and 34.3%)to Cinereous Vulture(Aegypius monachus)nesting site model.Wild ungulate distribution also contributed significantly(about 46%)to the Bearded Vulture(Gypaetus barbatus)model.This scavenger nests in the highlands of the Caucasus at a minimum distance of 5–10 km from anthropogenic facilities.In contrast,livestock as a food source was most important in colony distribution of Griffon Vulture(Gyps fulvus).The contribution of distances to settlements and agricultural facilities to the model was 45%.The optimal distance from Egyptian Vulture(Neophron percnopterus)nesting sites to settlements was only 3–10 km,to livestock facilities no more than 15 km with the factor contribution of about 57%.Excluding the wild ungulate availability,the ecological niches of studied vultures overlapped significantly.Despite similar foraging and nesting requirements,Caucasian vultures are not pronounced nesting and trophic competitors due to the abundance of nesting sites,anthropogenic food sources and successful niche sharing. 展开更多
关键词 Caucasian vultures Ecological niche differentiation Maxent nesting sites Species distribution models
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Nesting season,nest age,and disturbance,but not habitat characteristics,affect nest survival of Chinese grouse 被引量:1
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作者 Jin-Ming ZHAO Chen YANG +3 位作者 Ying-Qiang LOU Mei SHI Yun FANG Yue-Hua SUN 《Current Zoology》 SCIE CAS CSCD 2020年第1期29-37,共9页
Nest survival is a vital component of breeding success,and affects population dynamics,as the loss of nests is the main cause of reproductive failure in birds.To identify key factors for the conservation of Chinese gr... Nest survival is a vital component of breeding success,and affects population dynamics,as the loss of nests is the main cause of reproductive failure in birds.To identify key factors for the conservation of Chinese grouse Tetrastes sewerzowi,we tested the effects of nest concealment,nest age,nesting season,and habitat edge on nest daily survival rate(DSR)of Chinese grouse using 54 nests found at Lianhuashan Nature Reserve,Gansu,China,2009-2012.Moreover,we controlled for the effect of research activity by testing the effect of nest checks on DSR.Overall,mammal predation caused 93%of nest failures.DSR was 0.986±0.0038 in the constant model and the probability of a nest with a full clutch of 6 eggs surviving the entire 40-day nesting period was 0.526±0.090.DSR decreased with nest age and nesting season(from 19 May to 3 July).Mammals instead of avian predators being responsible for most nest failures suggest that nest sites might be selected to avoid visual avian predators,but not olfactory mammalian predators,and the decreasing trend of DSR with nest age and nesting season could attribute to an additive exposure effect.Moreover,nest checks conducted by investigators significantly lowered nest DSR,especially during the late period of nesting season and for older nests.Mammalian predators might locate the nest site by following the investigator's odor.Based on our results,we suggest that the late incubation stage is a particularly vulnerable period for nest survival of Chinese grouse and those researchers should adjust their activities around nests to balance the need of acquiring accurate data and decreasing nest predation risk. 展开更多
关键词 NEST age NEST CHECK nesting SEASON NEST survival program MARK Tetrastes sewerzowi
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HABITAT SUITABILITY INDEX MODELS: GREY HERON NESTING IN ZHALONG NATIONAL NATURE RESERVE 被引量:1
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作者 孙洪志 高中信 王丹 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第2期61-64,共4页
Grey heron (Ardea cimerca) is one kind of the great birds which are often seen in the northeast marsh area of P.R.China, and there are many grey herons to reproduce in Zhalong Nature Reserve from March to August annua... Grey heron (Ardea cimerca) is one kind of the great birds which are often seen in the northeast marsh area of P.R.China, and there are many grey herons to reproduce in Zhalong Nature Reserve from March to August annually. In this paper, through the inveingation of the grey herons nesting habitat and according to the water depth, vegetation type, cover density and plan heigh of the nesting place, the grey heron’s nesting habitat suitability index medes are established. The main model is s=(s1xs2xs3xs4)1/4,where s1 is the water depth suitability index, s2 is the vegetation type suitability index, s3 is the cover density index, sa is the plant height suitability index. These models provide a kind of reliable method for evaluating the habitat quality of the grey heron’s nesting. 展开更多
关键词 GREY HERON nesting HABITAT INDEX MODEL
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Sea Turtle Nesting: What Is Known and What Are the Challenges under a Changing Climate Scenario 被引量:1
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作者 Raquel A. M. São Miguel Rita Anastácio Mário J. Pereira 《Open Journal of Ecology》 2022年第1期1-35,共35页
The rate of climate change experienced globally in recent decades may compromise sea turtles’ survival;especially temperature increase, which is particularly fast, impacts life history characteristics, such as temper... The rate of climate change experienced globally in recent decades may compromise sea turtles’ survival;especially temperature increase, which is particularly fast, impacts life history characteristics, such as temperature-dependent sex determination (TSD), late maturity and sea turtles highly migratory nature. This review aims to identify and summarize the information that has been collected from 2009-2020 in order to aid future empirical studies that seek to fill these and other knowledge gaps, and subsequently assist conservationists in making multilevel decisions to protect sea turtle populations and species. In a summarized way the general knowledge acquired so far on the influence of environmental abiotic and biotic factors on nesting behaviour and hatching, emergence and survival successes of sea turtle hatchlings, was gathered. To accomplish this work, a search on Web of Science, Science Direct, NCBI/PubMed, and Google Scholar was carried out using the terms “sea turtles + climate change”. Published articles in the period 2009-2020 were selected, related to the nesting ecology of 5 species of sea turtles: <em>Caretta caretta</em>, <em>Eretmochelys imbricata</em>, <em>Dermochelys coriacea</em>,<em> Chelonia mydas</em>, <em>Lepidochelys olivacea</em>. Emphasis was also placed on geographical information and on population location (e.g. climatic conditions during the nesting season). These articles (N = 126) were analysed giving relevance to researcher’s data interpretations, comparisons with other researches, and the reached conclusions. An attempt was made to represent all 5 species of sea turtles when selecting articles on each of the environmental factors that influence sea turtle nesting: temperature, humidity, nesting substrate, gases, depth of the nest, sea surface temperature (SST), nest location on the beach, nesting phenology and geographic distribution of nesting habitats. The interaction between these parameters and their consequences on the terrestrial phase of reproduction are presented and discussed. 展开更多
关键词 Reproductive Ecology Sea Turtles Climate Change nesting Phenology and Geographic Distribution of nesting Habitats
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Green Turtle, <i>Chelonia mydas</i>, Nesting and Temperature Profile of the Nesting Beach at Huyong Island, the Similan Islands in Andaman Sea 被引量:1
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作者 Sarawoot Gomuttapong Winai Klom-In +3 位作者 Jirarach Kitana Putsatee Pariyanonth Kumthorn Thirakhupt Noppadon Kitana 《Natural Resources》 2013年第4期357-361,共5页
Global change in temperature is regarded as a serious natural disaster that may cause extinction of organisms. Green turtle, Chelonia mydas, is not only an endangered species but also a species with temperature depend... Global change in temperature is regarded as a serious natural disaster that may cause extinction of organisms. Green turtle, Chelonia mydas, is not only an endangered species but also a species with temperature dependent sex determination that could be affected by the global warming. In this study, nesting and temperature profile of C. mydas nesting beach at HuyongIsland, the most important nesting site of C. mydas in Andaman Sea of Thailand, were studied in order to monitor a potential effect of regional climate change on the green turtle nesting activity and habitat. Nesting activities were surveyed during May-August 2011 and temperature profiles of the nesting beach were monitored for 58 days during the normal incubation period of this species. The total of 25 nests with clutch size of 105 ± 25 eggs was found during this study period suggesting normal nesting activity of the green turtle. Temperature profile of the nesting beach showed similar trend among nests with no clear influence of the vegetation cover. Mean nest temperature at the middle-third period, corresponding to the temperature-sensitive period of C. mydas, ranged from 28.3°C to 28.9°C, suggesting a slightly male-biased sex ratio of the offspring. Overall, temperature profile of the nesting beach showed little or no indication of adverse effects of regional increase in temperature on nesting activity and egg incubation of the green turtle at this period. 展开更多
关键词 Conservation nesting Ecology Sea TURTLE Thermal Profile
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Nesting innovations allow population growth in an invasive population of rose-ringed parakeets
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作者 Dailos HERNANDEZ-BRITO Jose L.TELLA +1 位作者 Guillermo BLANCO Martina CARRETE 《Current Zoology》 SCIE CAS CSCD 2022年第6期617-626,共10页
Certain traits of recipient environments,such as the availability of limiting resources,strongly determine the establishment success and spread of non-native species.These limitations may be overcome through behaviora... Certain traits of recipient environments,such as the availability of limiting resources,strongly determine the establishment success and spread of non-native species.These limitations may be overcome through behavioral plasticity,allowing them to exploit alternative resources.Here,we show how a secondary cavity nester bird,the rose-ringed parakeet Psittacula krameri,innovates its nesting behavior as a response to the shortage of tree cavities for nesting in its invasive range in Tenerife(Canary Islands).We observed that some breeding pairs excavated their own nest cavities in palms,thus becoming primary cavity nester,whereas others occupied nests built with wood sticks by another invasive species,the monk parakeet Myiopsitta monachus.The use of these novel nesting strategies increased the number of breeding pairs by up to 52%over 6 years,contributing to a 128.8%increase of the whole population.Innovative nests were located at greater heights above ground and were more aggregated around conspecifics but did not result in greater breeding success than natural cavities.Occupation of monk parakeet colonies by rose-ringed parakeets also benefited the former species through a protective-nesting association against nest predators.Our results show how an invasive species innovate nesting behaviors and increase nest-site availability in the recipient environment,thus facilitating its population growth and invasion process.Potential behavioral innovations in other invasive rose-ringed parakeet populations may be overlooked,and should be considered for effective management plans. 展开更多
关键词 antipredator response behavioral flexibility biological invasions cavity nesters nesting innovation reproductive success
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Monitoring hawksbill turtle nesting sites in some protected areas from the Persian Gulf
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作者 Majid Askari Hesni Mohsen Rezaie-Atagholipour +7 位作者 Somaye Zangiabadi Mohammad Amin Tollab Mostafa Moazeni Hosein Jafari Mohammad Talebi Matin Ghasem Ghorbanzadeh Zafarani Mahtab Shojaei Abbas Motlaghnejad 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第12期43-51,共9页
Iranian nesting populations of the critically endangered hawksbill turtle(Eretmochelys imbricate) are some of the most important in the Indian Ocean. In this study, four of the most important hawksbill nesting grounds... Iranian nesting populations of the critically endangered hawksbill turtle(Eretmochelys imbricate) are some of the most important in the Indian Ocean. In this study, four of the most important hawksbill nesting grounds in the Persian Gulf, situated within three Iranian marine protected areas, were surveyed during nesting season,including Nakhiloo, Ommolgorm and Kharko Islands and the mainland beaches of the Naiband Marine-Coastal National Park(NMCNP). We present GIS maps of these key nesting grounds and describe sand texture of key nesting zones, along with conservation recommendations. About 9.2(28.3%) out of 32.5 km of all shores surveyed in this study were used by nesting hawksbill turtles follows: Nakhiloo: 1.4 km(52% of potential nesting area);Ommolgorm: 1.94 km(40%);Kharko: 3.4 km(28%), and NMCNP: 2.46 km(18.9%). The average nesting density was calculated as 131 nests/km at Nakhiloo, 76 nests/km at Ommolgorm, 7 nests/km at Kharko, and 15 nests per km at NMCNP. Highest nesting density was observed in Nakhiloo and Ommolgorm. It is thought that high hawksbill nesting density in these islands seems likely a result of limiting adequate nesting shores rather than the size of population, and also low density in Kharko and NMCNP more related to past and current pressures and low population density. With the exception of Ommolgorm Island, sands at the nesting grounds were well sorted.Grain size indicated that female hawksbill turtles in the Iranian Persian Gulf nest in sands that are generally mixed, with mean grain size ranging from coarse sands(0.4Φ;~0.5–1 mm) to fine sands(2Φ;~0.25 mm). We provide and discuss conservation recommendations and suggestions for future. 展开更多
关键词 marine protected areas marine turtles nesting sand texture GIS maps
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Two-Dimensional Nesting System Based on Hybrid Genetic Algorithm
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作者 WU Qingming YANG Wei ZHANG Qiang ZHOU Junjie 《Wuhan University Journal of Natural Sciences》 CAS 2009年第1期60-64,共5页
According to the cutting stock problem of 2-dimensional shapes, a nesting system (NS) based on hybrid genetic algorithm (HGA) is established. The system optimizes the sequence and angles of polygons with hybrid Ge... According to the cutting stock problem of 2-dimensional shapes, a nesting system (NS) based on hybrid genetic algorithm (HGA) is established. The system optimizes the sequence and angles of polygons with hybrid Genetic Algorithm to accomplish the superior solution. It nests the irregular shape directly without covering irregular shapes with a rectangle. It also improves the decoding strategy of 2-dimensional shapes nesting based on the classical bottom-left strategy, makes the new strategy be universal to convex polygons, concave polygons and line-circular composted polygons. 展开更多
关键词 nesting system hybrid genetic algorithm (HGA) regular and circular polygon bottom-left strategy
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Genetic Algorithms to the Nesting Problem in the Leather Manufacturing Industry
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作者 张玉萍 蒋寿伟 尹忠慰 《Journal of Donghua University(English Edition)》 EI CAS 2005年第1期90-96,共7页
The nesting problem in the leather manufacturing is the problem of placing a set of irregularly shaped pieces (called stencils) on a set of irregularly shaped surfaces (called leathers sheets). This paper presents a n... The nesting problem in the leather manufacturing is the problem of placing a set of irregularly shaped pieces (called stencils) on a set of irregularly shaped surfaces (called leathers sheets). This paper presents a novel and promising processing approach. After the profile of leather sheets and stencils is obtained with digitizer, the discretization makes the processing independent of the specific geometrical information. The constraints of profile are regarded thoroughly. A heuristic bottom-left placement strategy is employed to sequentially locate stencils on sheets. The optimal placement sequence and rotation are deterimined by genetic algorithms (GA). A natural concise encoding method is developed to satisfy all the possible requirements of the leather nesting problem. The experimental results show that the proposed algorithm can not only be applied to the normal two-dimensional nesting problem, but also especially suitable for the placement of multiple two-dimensional irregular stencils on multiple two-dimensional irregular sheets. 展开更多
关键词 leather nesting genetic algorithms two-dimensional geometry IRREGULAR discretization.
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Is nesting in closed nestboxes advantageous for the European Robin(Erithacus rubecula)?
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作者 Rimvydas Juškaitis 《Avian Research》 CSCD 2021年第2期208-217,共10页
Background:The European Robin(Erithacus rubecula)is eurytopic in its choice of nest site,which can be either half-open or closed,and situated either on the ground or at a height of several meters.On occasion,robins al... Background:The European Robin(Erithacus rubecula)is eurytopic in its choice of nest site,which can be either half-open or closed,and situated either on the ground or at a height of several meters.On occasion,robins also nest in closed nestboxes,though generally only solitary such cases are documented,albeit that dozens of such events can be recorded during the course of some long-term studies.However,until now,nobody has summarised the peculiarities of robins nesting in closed nestboxes.Methods:In the period 1978-2020,wooden tit and starling nestboxes were inspected regularly at five study sites in Lithuania,this totaling more than 18,000 nestbox-seasons.During these inspections,90 cases of robins nesting in the nestboxes were recorded.Publications on this topic from the entire robin distribution range were reviewed.Results:Robins prefer to nest in old large-sized fairly shallow nestboxes with wide entrance holes,for example starling nestboxes or tit nestboxes with enlarged entrance holes.Increased numbers of nestboxes being occupied by robins were recorded for 3-8 years in row.In Lithuania,nesting success in nestboxes is not higher than compared with nesting on the ground.Tree climbing mammals,Pine Martens(Martes martes),Hazel Dormice(Muscardinus avellanarius),Edible Dormice(Glis glis)and Forest Dormice(Dryomys nitedula),are the main predators of robin nests in nestboxes.Conclusions:Some geographic variation was found in the occurrence of robins nesting in nestboxes with more such cases recorded in central and southern parts of the range.Possibly robins are more philopatric in these parts of the range,with the same females or their offspring nesting in nestboxes for several years in row.In areas inhabited by dormice,nesting in closed nestboxes is not advantageous for robins. 展开更多
关键词 Erithacus rubecula European Robin Nestbox dimensions nesting success Predators
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A high incidence of non-cavity nesting in an introduced population of House Sparrows suggests that the species should not be constrained by cavity-nest site availability
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作者 Elizabeth Louise Sheldon Simon Charles Griffith 《Avian Research》 CSCD 2017年第4期202-209,共8页
Background: The House Sparrow(Passer domesticus) has undergone dramatic population declines in many parts of Europe.It has been widely hypothesised that a lack of cavity nest sites has contributed to this decline.Howe... Background: The House Sparrow(Passer domesticus) has undergone dramatic population declines in many parts of Europe.It has been widely hypothesised that a lack of cavity nest sites has contributed to this decline.However the idea of the House Sparrow being nest site limited is somewhat incompatible with the long history of nest site plasticity in the species.Methods: The nest-site selection in a population of non-native House Sparrows introduced to Australia from Europe just over 150 years ago was characterised.The prevalence of non-cavity nesting was quantified,and nest-site selection in terms of landscape and nesting structure were described.Results: Flexible nesting behaviors were reported over a range of different landscapes and a surprisingly high rate of nesting in vegetation(43%) was documented.Most nests found in vegetation were not in cavities,but were woven into the foliage and supported by branches and stems.Conclusion: The high rate of vegetation nesting indicates that in this introduced population,the House Sparrow is unlikely to be constrained by cavity-nest site availability.The high degree of nest site plasticity in the Australian population may suggest that European House Sparrows have the potential to shift away from their proclivity for cavity nests.Future work in Europe should examine the incidence of non-cavity nesting in House Sparrows more closely,and perhaps reconsider the idea that House Sparrows are nest-site constrained. 展开更多
关键词 Passer domesticus Cavity nests House Sparrow decline nesting plasticity
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