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Marine Predators Algorithm with Deep Learning-Based Leukemia Cancer Classification on Medical Images
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作者 Sonali Das Saroja Kumar Rout +5 位作者 Sujit Kumar Panda Pradyumna Kumar Mohapatra Abdulaziz S.Almazyad Muhammed Basheer Jasser Guojiang Xiong Ali Wagdy Mohamed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期893-916,共24页
In blood or bone marrow,leukemia is a form of cancer.A person with leukemia has an expansion of white blood cells(WBCs).It primarily affects children and rarely affects adults.Treatment depends on the type of leukemia... In blood or bone marrow,leukemia is a form of cancer.A person with leukemia has an expansion of white blood cells(WBCs).It primarily affects children and rarely affects adults.Treatment depends on the type of leukemia and the extent to which cancer has established throughout the body.Identifying leukemia in the initial stage is vital to providing timely patient care.Medical image-analysis-related approaches grant safer,quicker,and less costly solutions while ignoring the difficulties of these invasive processes.It can be simple to generalize Computer vision(CV)-based and image-processing techniques and eradicate human error.Many researchers have implemented computer-aided diagnosticmethods andmachine learning(ML)for laboratory image analysis,hopefully overcoming the limitations of late leukemia detection and determining its subgroups.This study establishes a Marine Predators Algorithm with Deep Learning Leukemia Cancer Classification(MPADL-LCC)algorithm onMedical Images.The projectedMPADL-LCC system uses a bilateral filtering(BF)technique to pre-process medical images.The MPADL-LCC system uses Faster SqueezeNet withMarine Predators Algorithm(MPA)as a hyperparameter optimizer for feature extraction.Lastly,the denoising autoencoder(DAE)methodology can be executed to accurately detect and classify leukemia cancer.The hyperparameter tuning process using MPA helps enhance leukemia cancer classification performance.Simulation results are compared with other recent approaches concerning various measurements and the MPADL-LCC algorithm exhibits the best results over other recent approaches. 展开更多
关键词 Leukemia cancer medical imaging image classification deep learning marine predators algorithm
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The Influence of Transgenic cry1Ab/cry1Ac,cry1C and cry2A Rice on Non-Target Planthoppers and Their Main Predators Under Field Conditions 被引量:14
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作者 HANYu XU Xue-liang MA Wei-hua YUAN Ben-qi WANG Hui LIU Fang-zhou WANG Man-qun WU Gang HUA Hong-xia 《Agricultural Sciences in China》 CAS CSCD 2011年第11期1739-1747,共9页
Transgenic Bt rice has been shown to be an effective means of controlling Lepidoptera pests of rice. However, the potential roles of transgenic rice on planthoppers and their predators need to be investigated before i... Transgenic Bt rice has been shown to be an effective means of controlling Lepidoptera pests of rice. However, the potential roles of transgenic rice on planthoppers and their predators need to be investigated before its commercialization. Population density, species dominance and population dynamics are important parameters of arthropods populations in field. So the impacts of three transgenic Bt rice strains expressing crylAb/crylAc, crylC and cry2A on population density, species dominance and population dynamics of three species of planthoppers (Nilaparvata lugens, Sogatella furcifera and Laodelphax striatellus) and their three main predators ( Cyrtorhinus lividipennis, Pirata subpiraticus and Theridium octomaculatum) were evaluated at three sites in Hubei Province, China, in the current study. The results showed that among three species of planthoppers, both in transgenic and non-transgenic rice field, the predominant species ofplanthoppers within phytophagous guild was S. furcifera at any site either growing season (46-50%). Significantly higher population density ofN. lugens was observed in T2A-1 field relative to Minghui 63 field at Wuxue in 2010. The species dominance of predator, P. subpiraticus, in TT51 field was significantly higher than that in T 1 C-19 and T2A-1 fields in 2009 at Xiaogan site. Sampling date significantly influenced six arthropods except for P. subpiraticus in 2010. The interaction between rice strain^sampling date had no significant adverse effects on the population dynamics of three species of planthoppers and their predators, except for several individual species in 2009. The interaction among rice strain^sampling date^sampling site also had no significant effect on six arthropods except for S. furcifera in 2009. The results indicated that transgenic Bt rice expressing crylAb/crylAc, cry2A and crylC had no significant adverse effects on the population dynamics of three planthoppers and their predators in most investigated data and sampling site. 展开更多
关键词 PLANTHOPPER PREDATOR transgenic Bt rice population dynamics species dominance population density
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Effects of Transgenic Bt+CpTI Cotton on Field Abundance of Non-Target Pests and Predators in Xinjiang, China 被引量:10
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作者 XUYao WU Kong-ming +7 位作者 LI Hao-bing LIU Jian DING Rui-feng WANG Fei Ahtam Uwayis LI Hai-qiang WANG Dong-mei CHEN Xue-xin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第9期1493-1499,共7页
Transgenic insect-resistant cotton is being increasingly planted in Xinjiang cotton-planting regions, where geographical climate conditions and species composition of pests and natural enemies are greatly unique in Ch... Transgenic insect-resistant cotton is being increasingly planted in Xinjiang cotton-planting regions, where geographical climate conditions and species composition of pests and natural enemies are greatly unique in China. Limited studies have been conducted on the ecological impacts of transgenic insect-resistant cotton, especially for transgenic double genes (Bt+CpTI) cotton, in this region. In this study, the potential effects of transgenic Bt+CpTI cotton on the seasonal abundance of non-target pests and predators were assessed from 2009 to 2011 in Korla, Xinjiang. The results showed that species composition and seasonal abundance of 5 groups of pests and 5 groups of predators were not significantly different between transgenic Bt+CpTI cotton and non-transgenic cotton every year. It suggests that transgenic Bt+CpTI cotton per se does not affect the population dynamics of non-target pests and predators on this crop in Xinjiang. 展开更多
关键词 transgenic Bt+CpTI cotton non-target pests predators XINJIANG
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Nest predators, nest-site selection and nest success of the Emei Shan Liocichla(Liocichla omeiensis), a vulnerable babbler endemic to southwestern China 被引量:8
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作者 Yiqiang Fu Benping Chen +1 位作者 Simon D.Dowell Zhengwang Zhang 《Chinese Birds》 CSCD 2016年第3期161-166,共6页
Background: The Emei Shan Liocichla(Liocichla omeiensis) is a globally vulnerable babbler, endemic to southwestern China. We investigated its nest predators, nest-site selection and nest success at the Laojunshan Nati... Background: The Emei Shan Liocichla(Liocichla omeiensis) is a globally vulnerable babbler, endemic to southwestern China. We investigated its nest predators, nest-site selection and nest success at the Laojunshan National Nature Reserve in Sichuan, China in order to identify the precise nesting-habitat requirements of the species, and to test whether the nest-site-selection cues, preferred by the Emei Shan Liocichla, are positively associated with nest success.Methods: We used infrared cameras to determine nest predators. We compared the microhabitat attributes between nest and random sites, as well as successful and failed nests. We used Binary Logistic Regression to determine the most important variables affecting nest-site selection of the Emei Shan Liocichla. We used the nest survival analysis in Program MARK to estimate daily nest survival rates(DSR). Nest success was calculated using the Mayfield method.Results: In total 56 nests were found. The DSR for all nests that contained at least one egg was 0.9564 ± 0.0091(95 % CI 0.9346–0.9711)(n = 40), while the total nest success was 27.5 %. We identified four categories of predators in 10 nest predation events, i.e. squirrels(n = 5), snakes(n = 3), raptors(n = 1) and wasps(n = 1). We found that:(1) nest predation was the primary reason for nest failure of the Emei Shan Liocichla,(2) tree cover, bamboo cover, liana abundance and distance to forest edge or gap were the most important variables affecting nest-site selection of this species, and(3) the nest-site-selection variables we measured appeared not to be positively associated with nest success.Conclusions: Our findings suggest that the Emei Shan Liocichla tended to select nest sites near forest edges or gaps with good concealment and that nest-site selection by this species was nonrandom but not necessarily adaptive. Reducing forest-edge development and protecting bamboo stands should be effective for conservation of this species. 展开更多
关键词 Nest predator Nest-site selection Nest success Liocichla omeiensis Laojunshan Nature Reserve
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Using endocarp-remains of seeds of wild apricot Prunus armeniaca to identify rodent seed predators 被引量:1
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作者 Hongmao ZHANG Wei WANG 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第6期396-400,共5页
Some rodent-dispersed seeds have a hard seed-coat(e.g.woody endocarp).Specific scrapes or dental marks on the hard seed-coat left by rodents when they eat these seeds can be used to identify seed predators.In this stu... Some rodent-dispersed seeds have a hard seed-coat(e.g.woody endocarp).Specific scrapes or dental marks on the hard seed-coat left by rodents when they eat these seeds can be used to identify seed predators.In this study we measured the morphological traits of endocarp-remains of seeds of wild apricot Prunus armeniaca used by Chinese white-bellied rats Niviventor confucianus and Korean field mice Apodemus peninsulae.We established their Fisher's linear discriminant functions to separate endocarp-remains between the two predators.A total of 90.0% of the endocarp-remains left by Korean field mice and 88.0% of those left by Chinese white-bellied rats were correctly classified.The overall percentage of correct classification was 89.0%.One hundred and sixty endocarp-remains of unknown what species predated them were classified using the functions.The method may allow more reliable quantitative studies of the effects of Chinese white-bellied rats and Korean field mice on seed consumption and dispersal of wild apricot and this study might be used for reference in other studies of seed predators identification on hard seeds. 展开更多
关键词 Seed dispersal Seed predation Small rodents Stepwise Fisher discriminant analysis
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Effects of Predators on the Belowground Life Stages (Prepupae and Pupae) of the Western Flower Thrips, <i>Frankliniella occidentalis</i>(Thripidae: Thysanoptera): A Review 被引量:1
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作者 Raymond A. Cloyd 《Advances in Entomology》 2019年第4期71-80,共10页
Western flower thrips, Frankliniella occidentalis, is a major cosmopolitan insect pest causing direct and indirect damage to greenhouse-grown horticultural crops. The primary way of managing western flower thrips popu... Western flower thrips, Frankliniella occidentalis, is a major cosmopolitan insect pest causing direct and indirect damage to greenhouse-grown horticultural crops. The primary way of managing western flower thrips populations is by routinely applying insecticides, which target the aboveground life stages: larvae and adult. However, insecticides are minimally effective against the pupal stages (prepupae and pupae) that reside in the growing medium or soil. Therefore, soil-dwelling biological control agents including: predatory mites [Stratiolaelaps scimitus and Hypoaspis = (Geolaelaps) aculeifer], and a rove beetle, Dalotia coriaria may be a viable option to induce mortality on the pupal stages. These predators will feed on the pupal stages of the western flower thrips and can provide mortality on a life stage that is tolerant of insecticide applications. However, these biological control agents need to be used in conjunction with other plant protection strategies, such as insecticides and/or biological control agents that target the aboveground life stages (larvae and adult) to effectively manage western flower thrips populations in greenhouse production systems. 展开更多
关键词 PREDATORY Mites Rove Beetle Growing Medium Biological Control Predation
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Natural predators of polyps of three scyphozoans:Nemopilema nomurai,Aurelia coerulea,and Rhopilema esculentum
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作者 Changsheng TANG Song SUN Fang ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第2期598-608,共11页
Jellyfish blooms have become a hot research topic in recent decades because they pose a serious threat to fisheries,coastal industries,tourism,and the marine ecosystem.The life cycle of scyphozoan jellyfish consists o... Jellyfish blooms have become a hot research topic in recent decades because they pose a serious threat to fisheries,coastal industries,tourism,and the marine ecosystem.The life cycle of scyphozoan jellyfish consists of a pelagic medusa stage and a benthic polyp stage,where asexual reproduction and strobilation of the polyps directly affect the abundance of ephyra and subsequently medusa abundance.The dynamics of polyps are affected by both environmental and biological factors,and predation by natural predators is one of the most important biological factors.Nemopilema nomurai,Aurelia coerulea,and Rhopilema esculentum are three scyphozoan species that are commonly found in Chinese coastal waters,and previous studies reported that the survivorship of polyps differs among the three species when they are exposed to the same benthic community.To identify potential natural predators of polyps of these three species in Chinese coastal waters and to determine whether the predation rates on polyps of the three species differ,we collected 39 species of macrozoobenthos from the Bohai Sea,Yellow Sea,and East China Sea from May 2014 to June 2016 and conducted predation tests and predation rate measurements.We found that the nudibranchs Pleurobranchaea novaezealandiae,Okenia plana,and Chromodoris tinctoria and the sea anemones Paracalliactis sinica,Calliactis japonica,Anthopleura incerta,and Anthopleura midori could prey on the polyps of all three scyphozoan species.The predation rates increased with the body length of the predators.The predations rates were also related to the polyp species,although the different predators showed no consistent preference for a particular species of polyp.Our results indicate that introducing predators to locations inhabited by polyps might be a way to control the benthic polyp populations and prevent subsequent jellyfish blooms. 展开更多
关键词 jellyfish bloom POLYPS predation rate predators
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Investigating how different classes of nest predators respond to the playback of the begging calls of nestling birds
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作者 Shilong Liu Qiao Xie +1 位作者 Aiwu Jiang Eben Goodale 《Avian Research》 SCIE CSCD 2022年第3期321-327,共7页
Begging brings benefits and costs for nestling birds:it can indicate their needs to their parents,but it can also be a cue used by predators to find the nest.The costs,like many variables related to nest predation,can... Begging brings benefits and costs for nestling birds:it can indicate their needs to their parents,but it can also be a cue used by predators to find the nest.The costs,like many variables related to nest predation,can be specific to what kinds of predators are present and their auditory capabilities.These costs and benefits could also be affected by human noise,as noise could disrupt communication to parents and eavesdropping by predators,although human-produced noise might be easily ignored if predators can hear high-frequency components of the begging.We studied nest predation on a generalist bird,the Red-whiskered Bulbul(Pycnonotus jocosus),in a tropical forest in which there are many kinds of nest predators,including birds,mammals and reptiles.In 20 natural nests in which artificial eggs were placed,and subsequently in 140 artificial nests,we broadcast recordings of begging nestlings,with and without traffic noise,at two volume levels.We hypothesized that playback would increase predation relative to a silent control,and that mixing in traffic noise with the begging would decrease predation,as the begging signal was masked.However,we hypothesized that some predators,particularly small mammals with sensitive high-frequency hearing,might ignore the traffic noise.We found that predation was lowest for the control treatment,and lower for treatments mixed with traffic noise than for those without it.Small mammals,however,showed an unexpected pattern,displaying less nest predation in the treatments with traffic noise.Our results demonstrate the human-associated noise can disturb nest predators and influence which kinds of predators use begging to locate nests. 展开更多
关键词 Anthropogenic noise BEGGING Bird reproduction Nest predation PLAYBACK
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Hybrid Marine Predators Optimization and Improved Particle Swarm Optimization-Based Optimal Cluster Routing in Wireless Sensor Networks(WSNs)
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作者 A.Balamurugan Sengathir Janakiraman +1 位作者 M.Deva Priya A.Christy Jeba Malar 《China Communications》 SCIE CSCD 2022年第6期219-247,共29页
Wireless Sensor Networks(WSNs)play an indispensable role in the lives of human beings in the fields of environment monitoring,manufacturing,education,agriculture etc.,However,the batteries in the sensor node under dep... Wireless Sensor Networks(WSNs)play an indispensable role in the lives of human beings in the fields of environment monitoring,manufacturing,education,agriculture etc.,However,the batteries in the sensor node under deployment in an unattended or remote area cannot be replaced because of their wireless existence.In this context,several researchers have contributed diversified number of cluster-based routing schemes that concentrate on the objective of extending node survival time.However,there still exists a room for improvement in Cluster Head(CH)selection based on the integration of critical parameters.The meta-heuristic methods that concentrate on guaranteeing both CH selection and data transmission for improving optimal network performance are predominant.In this paper,a hybrid Marine Predators Optimization and Improved Particle Swarm Optimizationbased Optimal Cluster Routing(MPO-IPSO-OCR)is proposed for ensuring both efficient CH selection and data transmission.The robust characteristic of MPOA is used in optimized CH selection,while improved PSO is used for determining the optimized route to ensure sink mobility.In specific,a strategy of position update is included in the improved PSO for enhancing the global searching efficiency of MPOA.The high-speed ratio,unit speed rate and low speed rate strategy inherited by MPOA facilitate better exploitation by preventing solution from being struck into local optimality point.The simulation investigation and statistical results confirm that the proposed MPOIPSO-OCR is capable of improving the energy stability by 21.28%,prolonging network lifetime by 18.62%and offering maximum throughput by 16.79%when compared to the benchmarked cluster-based routing schemes. 展开更多
关键词 Marine predators Optimization Algorithm(MPOA) Particle Swarm Optimization(PSO) Optimal Cluster-based Routing Cluster Head(CH)selection Wireless Sensor Networks(WSNs)
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Multi-Stage Improvement of Marine Predators Algorithm and Its Application
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作者 Chuandong Qin Baole Han 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期3097-3119,共23页
The metaheuristic algorithms are widely used in solving the parameters of the optimization problem.The marine predators algorithm(MPA)is a novel population-based intelligent algorithm.Although MPA has shown a talented... The metaheuristic algorithms are widely used in solving the parameters of the optimization problem.The marine predators algorithm(MPA)is a novel population-based intelligent algorithm.Although MPA has shown a talented foraging strategy,it still needs a balance of exploration and exploitation.Therefore,a multi-stage improvement of marine predators algorithm(MSMPA)is proposed in this paper.The algorithm retains the advantage of multistage search and introduces a linear flight strategy in the middle stage to enhance the interaction between predators.Predators further away from the historical optimum are required to move,increasing the exploration capability of the algorithm.In the middle and late stages,the searchmechanism of particle swarmoptimization(PSO)is inserted,which enhances the exploitation capability of the algorithm.This means that the stochasticity is decreased,that is the optimal region where predators jumping out is effectively stifled.At the same time,self-adjusting weight is used to regulate the convergence speed of the algorithm,which can balance the exploration and exploitation capability of the algorithm.The algorithm is applied to different types of CEC2017 benchmark test functions and threemultidimensional nonlinear structure design optimization problems,compared with other recent algorithms.The results show that the convergence speed and accuracy of MSMPA are significantly better than that of the comparison algorithms. 展开更多
关键词 Marine predators algorithm multi-stage strategy structural design optimization
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Plastering mud around the entrance hole affects the estimation of threat levels from nest predators in Eurasian Nuthatches
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作者 Jiangping Yu Li Zhang +5 位作者 Guodong Yi Keqin Zhang Jiyuan Yao Jian Fang Chao Shen Haitao Wang 《Avian Research》 SCIE CSCD 2021年第4期658-663,共6页
Background:For cavity-nesting birds,the nest entrance plays an important role in preventing predators from accessing nests.Several species of nuthatches use mud to narrow the entrance of cavities.In theory,the smaller... Background:For cavity-nesting birds,the nest entrance plays an important role in preventing predators from accessing nests.Several species of nuthatches use mud to narrow the entrance of cavities.In theory,the smaller the entrance hole size,the more effective it is against predators;however,few studies have tested whether narrowing the entrance hole size can affect the estimation of threat levels from nest predators in cavity-nesting birds.Methods:Using dummy experiments,we tested whether Eurasian Nuthatches(Sitta europaea,narrow the entrance hole of cavities)and Cinereous Tits(Parus cinereus,do not narrow the entrance hole,as a control)perform different nest defence behaviours against Common Chipmunks(Tamias sibiricus,small nest predator)and Red Squirrels(Sciurus vulgaris,larger nest predator).Results:Both nuthatches and tits exhibited stronger response behaviours(high dummy response scores)against chipmunks than against squirrels.Compared with tits,nuthatches exhibited more aggressive behaviours to chipmunks,but their responses to squirrels were similar.Conclusions:Nest defence behaviours of nuthatches to chipmunks differed from tits,and the results suggested that nuthatches might estimate threat levels of nest predators according to their narrowed entrance-hole size. 展开更多
关键词 Cavity-nesting birds Entrance-hole size Eurasian Nuthatches Nest defence behaviour Nest predator
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Shift in microhabitat use as a mechanism allowing the coexistence of victim and killer carnivore predators
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作者 Maria Viota Alejandro Rodriguez +1 位作者 Jose V.Lopez-Bao Francisco Palomares 《Open Journal of Ecology》 2012年第3期115-120,共6页
It has been suggested that spatial heterogeneity is key to the coexistence at local spatial scales of subordinate and dominant predator species by allowing the former to shift to more protective habitats when the risk... It has been suggested that spatial heterogeneity is key to the coexistence at local spatial scales of subordinate and dominant predator species by allowing the former to shift to more protective habitats when the risk of intraguild predation exists. Here, we show how the smaller carnivore Egyptian mongoose (Herpestes ichneumon) may coexist on a local scale with its intraguild pre- dator, the Iberian lynx (Lynx pardinus), by using places with different microhabitat character- istics. We expect that mongooses living within lynx home ranges will use denser and more protective habitats when active in order to di- minish their risk of being killed by lynx com- pared to those living in areas similar in vege- tation and prey availability but where lynx are absent. The scrubland cover of points used by mongooses outside lynx areas, and that of points located within lynx areas but not used by mongooses, were significantly lower than, or similar to, cover of points used by mongooses within lynx areas. The probability of finding mon- goose tracks was constant across levels of scrubland cover when lynx were absent, but more mongoose tracks were likely to be found in thicker scrubland within lynx areas, especially if these areas were intensively used by lynx. This result agrees with the hypothesis on shifts in microhabitat use of subordinate carnivores to prevent fatal or risky encounters with dominant ones. 展开更多
关键词 Carnivore Coexistence Egyptian Mongoose Iberian Lynx Interspecific Competition Intraguild Predation Microhabitat Shift Spatial Heterogeneity
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基于多维气象信息时空融合和MPA-VMD的短期电力负荷组合预测模型 被引量:2
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作者 王凌云 周翔 +2 位作者 田恬 杨波 李世春 《电力自动化设备》 EI CSCD 北大核心 2024年第2期190-197,共8页
为提高电力负荷预测精度,需考虑区域内不同地区多维气象信息对电力负荷影响的差异性。在空间维度上,提出多维气象信息时空融合的方法,利用Copula理论将多座气象站的风速、降雨量、温度、日照强度等气象信息与电力负荷进行非线性耦合分... 为提高电力负荷预测精度,需考虑区域内不同地区多维气象信息对电力负荷影响的差异性。在空间维度上,提出多维气象信息时空融合的方法,利用Copula理论将多座气象站的风速、降雨量、温度、日照强度等气象信息与电力负荷进行非线性耦合分析并实现时空融合。在时间维度上,采用海洋捕食者算法(MPA)实现变分模态分解(VMD)核心参数的自动寻优,并采用加权排列熵构造MPA-VMD适应度函数,实现负荷序列的自适应分解。通过将时间维度各分量与空间维度各气象信息进行融合构造长短期记忆(LSTM)网络模型与海洋捕食者算法-最小二乘支持向量机(MPA-LSSVM)模型的输入集,得到各分量预测结果,根据评价指标选择各分量对应的预测模型,重构得到整体预测结果。算例分析结果表明,所提预测模型优于传统预测模型,有效提高了电力负荷预测精度。 展开更多
关键词 短期电力负荷预测 海洋捕食者算法 时空融合 COPULA理论 变分模态分解
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考虑最小平均包络熵负荷分解的最优Bagging集成超短期多元负荷预测 被引量:3
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作者 姜飞 林政阳 +3 位作者 王文烨 王小明 奚振乾 郭祺 《中国电机工程学报》 EI CSCD 北大核心 2024年第5期1777-1788,I0009,共13页
多元负荷预测技术是保证综合能源系统(integrated energy system,IES)供需平衡与稳定运行的关键基石。但具有强随机性与波动性的IES负荷加剧了超短期多元负荷准确预测的难度。为此,提出考虑最小平均包络熵负荷分解的最优Bagging集成超... 多元负荷预测技术是保证综合能源系统(integrated energy system,IES)供需平衡与稳定运行的关键基石。但具有强随机性与波动性的IES负荷加剧了超短期多元负荷准确预测的难度。为此,提出考虑最小平均包络熵负荷分解的最优Bagging集成超短期多元负荷预测方法。构建基于最小平均包络熵的变分模态分解参数优化模型,将IES多元负荷分解为本征模态分量集合;基于统一信息系数法筛选多元负荷预测的日历、气象与负荷强相关特征;结合负荷本征模态分量集合、日历规则、气象环境与负荷数据,构建Bagging集成超短期多元负荷预测模型,并建立基于平均绝对百分比误差与决定系数的集成策略优化模型,进而得到最优集成策略与最终预测结果。以美国亚利桑那州立大学坦佩校区IES为对象展开仿真验证,结果表明,所提方法的电、热、冷负荷预测平均绝对百分比误差分别为1.9486%、2.0585%、2.5331%,相比其他预测方法具有更高准确率。 展开更多
关键词 多元负荷预测 综合能源系统 集成学习 海洋捕食者算法 包络熵
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家鸡对丝带凤蝶性二型体色的反应 被引量:1
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作者 张增焘 喻龙 +1 位作者 焦晓国 常海珍 《湖北大学学报(自然科学版)》 CAS 2024年第1期141-148,F0003,共9页
旨在明确丝带凤蝶成虫Sericinus montelus Gray在全光谱范围内存在性二型体色,评估鸟类对丝带凤蝶性二型体色的识别度,推测性二型体色是否对雌雄丝带凤蝶个体的生存概率产生影响。先用光谱检测仪测量丝带凤蝶雌雄成虫的反射光谱,分析反... 旨在明确丝带凤蝶成虫Sericinus montelus Gray在全光谱范围内存在性二型体色,评估鸟类对丝带凤蝶性二型体色的识别度,推测性二型体色是否对雌雄丝带凤蝶个体的生存概率产生影响。先用光谱检测仪测量丝带凤蝶雌雄成虫的反射光谱,分析反射光谱特征;再通过家鸡Gallus gallus domesticus视觉模型估算丝带凤蝶雌雄体色与预设背景的颜色差异。最后以小鸡为捕食者设计行为学试验,观测小鸡捕食雌雄丝带凤蝶成虫的行为反应。反射光谱测量结果显示雌雄丝带凤蝶在可见光和紫外波段都具有体色差异,雄性在前后翅白斑测量点上的亮度明显高于雌性。鸟类视觉模型结果表明,雄性丝带凤蝶所有测量点在明暗视觉(远距离)和颜色视觉(近距离)中的识别度值都高于识别阈值3,捕食者容易识别;但是雌性丝带凤蝶前翅和后翅黄白斑识别度值在明暗视觉和颜色视觉中都介于1与3之间,捕食者不易区分。捕食行为试验数据分析发现,捕食者发现猎物的潜伏时间及攻击潜伏时间没有显著差异,但小鸡啄食雄性猎物的次数及处理时间都显著高于雌性猎物。由此可见,与雌性丝带凤蝶相比,雄性在全光谱范围内的确具有更加亮丽的体色,但这种亮丽的视觉信号更易吸引鸟类捕食者的注意,带来了更高的捕食风险。 展开更多
关键词 家鸡 丝带凤蝶 性二型 捕食 反射光谱 视觉模型
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具有避难效应和非局部被捕食效应的捕食系统斑图形态研究
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作者 王彩云 李静 +1 位作者 杨瑞兰 兰旺森 《工程数学学报》 CSCD 北大核心 2024年第4期727-740,共14页
具有避难效应的捕食–食饵反应扩散模型是一类重要的种群动力学模型,其斑图形态为研究种群数量时空分布提供关键信息。建立了一个具有避难效应和非局部被捕食效应的Leslie-Gower捕食–食饵反应扩散模型。首先,通过线性稳定性分析和Turin... 具有避难效应的捕食–食饵反应扩散模型是一类重要的种群动力学模型,其斑图形态为研究种群数量时空分布提供关键信息。建立了一个具有避难效应和非局部被捕食效应的Leslie-Gower捕食–食饵反应扩散模型。首先,通过线性稳定性分析和Turing失稳分析分别推导出正平衡点局部稳定及Turing失稳的条件。其次,通过数值模拟分别展示了食饵斑图形态随非局部被捕食效应和避难效应变化而演化的情况。最后,通过分析捕食者和食饵种群空间平均密度与非局部被捕食效应和避难效应参数的变化关系,研究表明:食饵种群数量随着非局部效应的增强而增大,捕食者种群数量随着非局部效应的增强而减少,说明非局部被捕食效应在促进食饵密度增长的同时,抑制捕食者种群的增长;捕食者和食饵种群的数量均随避难效应的增强而增大,说明较强避难效应对食饵种群具有庇护作用,并能促进捕食者和食饵种群持续共存。结论有助于人们更好地从数学层面理解非局部效应和避难效应对捕食者和食饵种群斑图形态影响的规律。 展开更多
关键词 避难效应 非局部被捕食效应 斑图 捕食者–食饵模型 反应扩散系统
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山大齿猛蚁和日本弓背蚁对小地老虎的捕食行为
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作者 高冬梅 皇甫佳一 郭萧 《中国农业科学》 CAS CSCD 北大核心 2024年第5期909-918,共10页
【目的】小地老虎(Agrotis ipsilon)是粮食和经济作物的重要地下害虫之一。论文旨在明确山大齿猛蚁(Odontomachus monticola)和日本弓背蚁(Camponotus japonicus)对小地老虎的捕食特性,丰富小地老虎生物防治技术手段,降低小地老虎防治... 【目的】小地老虎(Agrotis ipsilon)是粮食和经济作物的重要地下害虫之一。论文旨在明确山大齿猛蚁(Odontomachus monticola)和日本弓背蚁(Camponotus japonicus)对小地老虎的捕食特性,丰富小地老虎生物防治技术手段,降低小地老虎防治成本与化学农药用量。【方法】在猎物被土壤覆盖和裸露两种自然条件下,观察并统计山大齿猛蚁和日本弓背蚁在1、6、12、24和48 h内对不同虫态小地老虎的捕食选择性、捕食方式以及捕食致死率;在室内,利用两种蚂蚁的试验种群开展捕食行为序列特征研究。通过统计分析,明确两种蚂蚁捕食行为差异及控害特点。【结果】日本弓背蚁对小地老虎卵的致死率较低,48 h累计致死率仅为12.67%;山大齿猛蚁不取食小地老虎卵。两种蚂蚁对小地老虎幼虫和蛹的控制效果超过49%,最高达98.67%,且控制效果随小地老虎龄期增长而降低。山大齿猛蚁和日本弓背蚁捕食行为序列存在一定差异:两种蚂蚁对小地老虎低龄幼虫均以直接搬运为主;对体型较大的小地老虎高龄幼虫,日本弓背蚁具有试探、攻击、召唤同伴、猎物切割、群体搬运等行为,呈现出明显的群体性行为;而山大齿猛蚁对大型猎物的捕食行为较为单一,未观察到召唤同伴、群体搬运等行为,群体捕食行为不明显。两种蚂蚁对小地老虎捕食行为的差异也体现在捕食方式和对小地老虎的致死率方面:日本弓背蚁对小地老虎低龄幼虫多直接搬运回巢,捕食效率极高,对小地老虎高龄幼虫多以集体捕猎;山大齿猛蚁捕猎小地老虎高龄幼虫时丢弃比例较高,但因叮咬蜇刺,逃脱捕猎的小地老虎幼虫死亡率较高。此外,土壤覆盖极大地影响蚂蚁对小地老虎幼虫的发现,山大齿猛蚁和日本弓背蚁仅能发现地表猎物,不具备探测地下猎物的能力。【结论】日本弓背蚁和山大齿猛蚁对小地老虎幼虫和蛹均有较好的控制作用,小地老虎虫龄越低控制效果越好,两种蚂蚁对小地老虎高龄幼虫捕食行为存在一定差异,但不影响对小地老虎的控制效果。 展开更多
关键词 蚂蚁 地下害虫 小地老虎 致死率 捕食行为序列 天敌昆虫
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长白山阔叶红松林传播前种子昆虫捕食的研究
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作者 赵涛 吴文兰 +3 位作者 王晓雪 徐雨 房帅 张凯 《四川动物》 北大核心 2024年第2期154-162,共9页
昆虫捕食种子是种子死亡的一个主要原因,会影响植物种群更新和群落物种组成。传播前种子昆虫捕食的研究较为稀少,且大多为针对个别优势种的短期研究,限制了对于群落水平上传播前种子捕食的理解。本研究分析长白山阔叶红松林25 hm~2样地... 昆虫捕食种子是种子死亡的一个主要原因,会影响植物种群更新和群落物种组成。传播前种子昆虫捕食的研究较为稀少,且大多为针对个别优势种的短期研究,限制了对于群落水平上传播前种子捕食的理解。本研究分析长白山阔叶红松林25 hm~2样地中2020—2021年的种子雨,研究种子昆虫捕食率及其影响因素。所分析的5种乔木种子均遭到昆虫捕食,昆虫捕食率在物种和采集批次间差异较大(0~33.33%),年均昆虫捕食率为8.76%~14.39%。肉质果种子的昆虫捕食率显著低于干果(df=1,χ~2=20.76,P<0.001),种子产量的年际变异系数与昆虫捕食率呈显著负相关(df=1,χ~2=13.01,P<0.001),重量越轻的种子的昆虫捕食率越高(df=1,χ~2=10.54,P=0.001)。本研究表明,传播前种子昆虫捕食在长白山阔叶红松林群落中普遍存在,并且揭示了影响因素、讨论了潜在的影响机制。本研究有助于增进对于传播前种子昆虫捕食及其生态和演化意义的理解。 展开更多
关键词 种实昆虫 传播前种子 种子捕食 大年结实 昆虫捕食率
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基于VMD-IMPA-SVM的超短期风电功率预测 被引量:2
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作者 刘金朋 邓嘉明 +2 位作者 高鹏宇 刘胡诗涵 孙思源 《智慧电力》 北大核心 2024年第7期24-31,79,共9页
针对风力发电强波动性带来的预测精度不高问题,构建一种基于变模态分解(VMD)、灰狼优化算法(GWO)、海洋捕食者算法(MPA)和支持向量机(SVM)的组合预测模型。采用GWO对VMD的模态数和惩罚因子进行寻优,将原始功率序列分解为子序列进行降噪... 针对风力发电强波动性带来的预测精度不高问题,构建一种基于变模态分解(VMD)、灰狼优化算法(GWO)、海洋捕食者算法(MPA)和支持向量机(SVM)的组合预测模型。采用GWO对VMD的模态数和惩罚因子进行寻优,将原始功率序列分解为子序列进行降噪处理;运用对立学习和柯西变异等方法改进MPA的种群生成与变异方式,得到改进MPA(IMPA)并优化SVM中的核参数与惩罚参数,进而构建VMD-IMPA-SVM组合预测模型,对各子序列进行预测并叠加得到最终预测值。实际算例分析表明,所提组合预测模型具有较高的预测精度,同时具备强鲁棒性。 展开更多
关键词 风电功率预测 变模态分解 海洋捕食者算法 支持向量机 灰狼优化算法
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北京城市绿地节肢动物多样性与微环境因子关系
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作者 王琦 任斌斌 +4 位作者 王月宾 邵金丽 李薇 王建红 温俊宝 《华中农业大学学报》 CAS CSCD 北大核心 2024年第6期161-170,共10页
为厘清节肢动物多样性与绿地微环境因子间关系,进而促进城市绿地生物多样性,利用截获器法采集了北京市三环内6个中小型公园的节肢动物种群,应用Pearson相关性分析方法、回归分析、主成分分析探究节肢动物及其天敌多样性与绿地微环境因... 为厘清节肢动物多样性与绿地微环境因子间关系,进而促进城市绿地生物多样性,利用截获器法采集了北京市三环内6个中小型公园的节肢动物种群,应用Pearson相关性分析方法、回归分析、主成分分析探究节肢动物及其天敌多样性与绿地微环境因子间的关系。结果显示:节肢动物中蚜科为优势科,占总多度的52.12%;食蚜天敌昆虫中菜蚜茧蜂Semidalis rapae、广重粉蛉Diaeretiella aleyrodiformis为优势种,分别占总多度的27.73%和23.92%;天敌多度、丰度、香农-维纳指数在不同样地间差异显著。相关分析表明花期植物面积、丰度和香农-维纳指数与节肢动物多度(P<0.001)、食蚜天敌昆虫丰度(P<0.001)及多度(P<0.001)呈显著正相关,与节肢动物香农-维纳指数呈显著负相关(P<0.001),施药频次和施药剂量比与节肢动物多度呈显著正相关(P<0.001)。主成分分析结果显示施药剂量比、花期植物面积、施药频次、花期植物均匀度、花期植物香农-维纳多样性和花期植物丰度是影响绿地节肢动物科多样性的主要微环境因子。RDA分析结果显示花期植物面积、均匀度、香农-维纳多样性和丰度与节肢动物及食蚜天敌昆虫的多度显著正相关,与节肢动物多样性显著负相关。 展开更多
关键词 城市绿地 节肢动物 天敌昆虫 生物多样性 微环境
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