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Dieback of managed spruce stands in western Germany promotes beetle diversity
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作者 Eva Plath Chantal Trauth +2 位作者 Jan Gerhards Laura Griebel Klaus Fischer 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期55-71,共17页
Biodiversity loss is a significant problem at a global scale and may be amplified by climate change.In recent years,coniferous forests have had substantial die-back across Europe due to drought and subsequent bark-bee... Biodiversity loss is a significant problem at a global scale and may be amplified by climate change.In recent years,coniferous forests have had substantial die-back across Europe due to drought and subsequent bark-beetle outbreaks.As many studies on the consequences of disturbance and subsequent management have focused on natural stands,management implications for managed spruce stands are not well understood,even though such stands are widespread throughout Europe.In this study,beetle taxonomy,conservation value,and community com-position are compared among spruce plantations and four post-disturbance management approaches:standing dead-wood,lying deadwood,clear cuts,and long-term succession.Diversity and community composition differed significantly among management categories,while different beetle fami-lies responded similarly.Intact spruce stands harbored the lowest beetle diversity while the highest taxonomic diver-sity and conservation value was on clear cuts and stands with lying or standing deadwood.The proportion of forest specialists was highest in successional forests.In summary,different forest management categories harbored distinct beetle communities at the family-,species-,and ecological guild levels.Therefore,post-disturbance management should consider the landscape scale and include different management types.This enhances landscape heterogeneity and thus overall biodiversity but could also mitigate negative impacts of natural disturbances on ecosystem services. 展开更多
关键词 Bark-beetle outbreak Forest dieback SPRUCE DEADWOOD Nature conservation beetle biodiversity-Coleoptera Coniferous forests
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The rate of deadwood decomposition processes in tree stand gaps resulting from bark beetle infestation spots in mountain forests
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作者 Ewa Błonska Adam Gorski Jarosław Lasota 《Forest Ecosystems》 SCIE CSCD 2024年第3期339-346,共8页
Decaying wood is an essential element of forest ecosystems and it affects its other components.The aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in ... Decaying wood is an essential element of forest ecosystems and it affects its other components.The aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in the gaps formed in the montane forest stands.The research was carried out in the Babiog orski National Park.The research plots were marked out in the gaps of the stands,which were formed as a result of bark beetle gradation.Control plots were located in undisturbed stands.The research covered wood of two species–spruce and beech in the form of cubes with dimensions of 50 mm×50 mm×22 mm.Wood samples were placed directly on the soil surface and subjected to laboratory analysis after 36 months.A significant influence of the wood species and the study plot type on the physicochemical properties of the tested wood samples was found.Wood characteristics strongly correlated with soil moisture.A significantly higher mass decline of wood samples was recorded on the reference study plots,which were characterized by more stable moisture conditions.Poorer decomposition of wood in the gaps regardless of the species is related to lower moisture.The wood species covered by the study differed in the decomposition rate.Spruce wood samples were characterized by a significantly higher decomposition rate compared to beech wood samples.Our research has confirmed that disturbances that lead to the formation of gaps have a direct impact on the decomposition process of deadwood. 展开更多
关键词 Bark beetle BEECH Decomposition rate Forest ecosystem Mass decline SPRUCE Woody debris
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Applying an Improved Dung Beetle Optimizer Algorithm to Network Traffic Identification
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作者 Qinyue Wu Hui Xu Mengran Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期4091-4107,共17页
Network traffic identification is critical for maintaining network security and further meeting various demands of network applications.However,network traffic data typically possesses high dimensionality and complexi... Network traffic identification is critical for maintaining network security and further meeting various demands of network applications.However,network traffic data typically possesses high dimensionality and complexity,leading to practical problems in traffic identification data analytics.Since the original Dung Beetle Optimizer(DBO)algorithm,Grey Wolf Optimization(GWO)algorithm,Whale Optimization Algorithm(WOA),and Particle Swarm Optimization(PSO)algorithm have the shortcomings of slow convergence and easily fall into the local optimal solution,an Improved Dung Beetle Optimizer(IDBO)algorithm is proposed for network traffic identification.Firstly,the Sobol sequence is utilized to initialize the dung beetle population,laying the foundation for finding the global optimal solution.Next,an integration of levy flight and golden sine strategy is suggested to give dung beetles a greater probability of exploring unvisited areas,escaping from the local optimal solution,and converging more effectively towards a global optimal solution.Finally,an adaptive weight factor is utilized to enhance the search capabilities of the original DBO algorithm and accelerate convergence.With the improvements above,the proposed IDBO algorithm is then applied to traffic identification data analytics and feature selection,as so to find the optimal subset for K-Nearest Neighbor(KNN)classification.The simulation experiments use the CICIDS2017 dataset to verify the effectiveness of the proposed IDBO algorithm and compare it with the original DBO,GWO,WOA,and PSO algorithms.The experimental results show that,compared with other algorithms,the accuracy and recall are improved by 1.53%and 0.88%in binary classification,and the Distributed Denial of Service(DDoS)class identification is the most effective in multi-classification,with an improvement of 5.80%and 0.33%for accuracy and recall,respectively.Therefore,the proposed IDBO algorithm is effective in increasing the efficiency of traffic identification and solving the problem of the original DBO algorithm that converges slowly and falls into the local optimal solution when dealing with high-dimensional data analytics and feature selection for network traffic identification. 展开更多
关键词 Network security network traffic identification data analytics feature selection dung beetle optimizer
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The diameter of beech snags is an important factor for saproxylic beetle richness: Implications for forest management and conservation 被引量:1
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作者 Václav Zumr Oto Nakládal +1 位作者 Lukás Bílek JiríRemes 《Forest Ecosystems》 SCIE CSCD 2023年第5期635-645,共11页
Snags are an important component of beech forests that promote biodiversity.However,their occurrence is completely marginal in managed stands.Creating snags in these stands would greatly enhance biodiversity.We invest... Snags are an important component of beech forests that promote biodiversity.However,their occurrence is completely marginal in managed stands.Creating snags in these stands would greatly enhance biodiversity.We investigated whether snag dimensions were important for saproxylic beetle richness since they were easily transferable parameters to forest management and assessed the presence of other snag microhabitats affecting beetle communities.Data collection was performed using passive flight traps placed on thirty snags in a recent beech reserve.A total of 6706 adults belonging to 231 saproxylic species(53 Red List species,23%)were captured.The results showed that the most important snag parameters were the diameter(thickness)and canopy openness of the surrounding stands.The occurrence of Fomes fomentarius,the volume of snag and decay class 3 were marginally significant in terms of the preference of all saproxylic species.Alpha diversity was reduced by an advanced degree of decay and a surprisingly deep stem cavity.After dividing snag thickness into categories(<35 cm;35–70 cm and>70 cm DBH),we found that categories with snag diameter greater than 35 cm showed little differences in all saproxylic and Red List species richness and diversity indices and exhibited the highest similarity in beetle communities.Regarding recommendations to forest managers in terms of optimization and simplification of practical procedures,we suggest actively creating high stumps to act as snags greater than 35 cm in DBH diameter to promote biodiversity in beech management stands. 展开更多
关键词 DEADWOOD Coleoptera Biodiversity Active management Endangered beetles
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Evaluation of trap effi ciency for the Asian longhorned beetle,Anoplophora glabripennis
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作者 Junxin Yan Yantao Zhou +5 位作者 Dun Jiang Yaru Lü Yingsheng Liu Mengmeng Yu Aijun Zhang Shanchun Yan 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期1133-1144,共12页
The Asian longhorned beetle(ALB),Anoplophora glabripennis,is a well-known stem borer with high polyphagous properties causing frequent outbreaks in northeast China.An attractant-based trap is needed to improve the sen... The Asian longhorned beetle(ALB),Anoplophora glabripennis,is a well-known stem borer with high polyphagous properties causing frequent outbreaks in northeast China.An attractant-based trap is needed to improve the sensitivity,reliability,and effi ciency for detection of the beetle.In this study,the eff ects of attractants,trap types and color synergy of a trapping system were evaluated.Attractant blends comprised of the male-produced,two-component pheromone plus plant volatiles were used in the fi eld in Hengshui city.Plant volatiles(e.g.,1-pentanol,and 2-pentanol)in combination with male pheromones increased the mean number of trapped ALB compared to the pheromone alone.Males responded better than females to traps baited with plant volatiles alone,whereas traps emitting plant volatiles plus pheromone,regardless of trap type,captured more females than males.The ALB-trapping effi ciency of a modifi ed fl ight intercept panel trap was more than ten times as high as a woodborer panel trap and 1.2 times a fl ight intercept panel trap.The 1-pentanol and 2-pentanol attractants alone or in combination with male-produced pheromone were more eff ective for monitoring ALB than common lures.In laboratory Y-tube olfactometer experiments,the color brown was better at increasing attraction of both males and females to 1-pentanol,2-pentanol,1-pentanol+pheromone,and 2-pentanol+pheromone compared to the clear-glass control arm.The fi ndings provide a reliable and eff ective trap system to monitor ALB infestations. 展开更多
关键词 Asian longhorned beetle Trap design Visual cue Male-produced pheromone Plant volatiles Integrated pest management
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黑蜣(Bess beetle)纤维素酶的组分及其特性分析
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作者 池雅琴 朱静 +1 位作者 段旭 聂恒 《现代农业科技》 2011年第3期17-19,共3页
以30日龄的黑蜣幼虫为材料,对其整体匀浆后组织液中的纤维素酶组成及活性进行了分析。结果表明:黑蜣体内存在内切β-1,4-葡聚糖酶(Cx酶)、β-葡萄糖苷酶;β-葡萄糖苷酶和Cx酶的最适宜温度为分别为40℃和50℃;Cx酶和β-葡萄糖苷酶分别在p... 以30日龄的黑蜣幼虫为材料,对其整体匀浆后组织液中的纤维素酶组成及活性进行了分析。结果表明:黑蜣体内存在内切β-1,4-葡聚糖酶(Cx酶)、β-葡萄糖苷酶;β-葡萄糖苷酶和Cx酶的最适宜温度为分别为40℃和50℃;Cx酶和β-葡萄糖苷酶分别在pH值为6.4和5.2时具有最大的活力;β-葡萄糖苷酶和Cx酶的最适宜反应时间为80 min。Cx酶具有比β-葡萄糖苷酶更强的温度适应性,在30~50℃温度范围内可维持最大酶活力的66.20%。 展开更多
关键词 黑蜣 纤维素酶 性质 酶活力
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Restudies on Body Surface of Dung Beetle and Application of Its Bionics Flexible Technique 被引量:12
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作者 Jiurong Sun 1, Jianqiao Li 2, Hong Cheng 1, Zhendong Dai 3, Luquan Ren 2 1.College of Life Sciences, Peking University, Beijing, 100871,P.R. China 2.Key Laboratory of Terrain-Machine Bionics Engineering (Ministry of Education,China), Jilin University at Nanling Campus, Changchun, 130022,P.R.China 3.College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016,P.R.China 《Journal of Bionic Engineering》 SCIE EI CSCD 2004年第1期53-60,共8页
A scanning electron microscope was used to observe the structures of the setae on the surface of a dung beetle Copris ochus, Motschulsky. There are lots of setae on the body surface, especially on the ventral part sur... A scanning electron microscope was used to observe the structures of the setae on the surface of a dung beetle Copris ochus, Motschulsky. There are lots of setae on the body surface, especially on the ventral part surface and lateral to the legs which are different in size, arrangement and shape. These setae have different lengths and many thorns on the whole seta. The top ends of these setae stand up without furcations which direct uprightly towards the surface of the touched soil. By the method of removing these setae, getting the insect weight before and after digging into the dung we affirm farther that the setae on the beetle body surface form the anti-stick and non-adherent gentle interface. The soil machines and components made by imitating the gentle body surface of beetles have favorable non-adherent results. 展开更多
关键词 dung beetle SETA flexible surface scanning electron microscopy BIONICS soil adhesion
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Endoscopic submucosal dissection for early esophageal neoplasms using the stag beetle knife 被引量:7
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作者 Toshio Kuwai Toshiki Yamaguchi +10 位作者 Hiroki Imagawa Ryoichi Miura Yuki Sumida Takeshi Takasago Yuki Miyasako Tomoyuki Nishimura Sumio Iio Atsushi Yamaguchi Hirotaka Kouno Hiroshi Kohno Sauid Ishaq 《World Journal of Gastroenterology》 SCIE CAS 2018年第15期1632-1640,共9页
AIM To determine short-and long-term outcomes of endoscopic submucosal dissection(ESD) using the stag beetle(SB) knife, a scissor-shaped device.METHODS Seventy consecutive patients with 96 early esophageal neoplasms, ... AIM To determine short-and long-term outcomes of endoscopic submucosal dissection(ESD) using the stag beetle(SB) knife, a scissor-shaped device.METHODS Seventy consecutive patients with 96 early esophageal neoplasms, who underwent ESD using a SB knife at Kure Medical Center and Chugoku Cancer Center, Japan, between April 2010 and August 2016, were retrospectively evaluated. Clinicopathological characteristics of lesions and procedural adverse events were assessed. Therapeutic success was evaluated on the basis of en bloc, histologically complete, and curative or non-curative resection rates. Overall and tumor-specific survival, local or distant recurrence, and 3-and 5-year cumulative overall metachronous cancer rates were also assessed.RESULTS Eligible patients had dysplasia/intraepithelial neoplasia(22%) or early cancers(squamous cell carcinoma, 78%). The median procedural time was 60 min and on average, the lesions measured 24 mm in diameter, yielding 33-mm tissue defects. The en bloc resection rate was 100%, with 95% and 81% of dissections deemed histologically complete and curative, respectively. All procedures were completed without accidental incisions/perforations or delayed bleeding. During follow-up(mean, 35 ± 23 mo), no local recurrences or metastases were observed. The 3-and 5-year survival rates were 83% and 70%, respectively, with corresponding rates of 85% and 75% for curative resections and 74% and 49% for noncurative resections. The 3-and 5-year cumulative rates of metachronous cancer in the patients with curative resections were 14% and 26%, respectively.CONCLUSION ESD procedures using the SB knife are feasible, safe, and effective for treating early esophageal neoplasms, yielding favorable short-and long-term outcomes. 展开更多
关键词 Neoplasms STAG beetle KNIFE ESOPHAGEAL Endoscopic SUBMUCOSAL DISSECTION Outcome measures
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Factors impacting nanoindentation testing results of the cuticle of dung beetle Copris ochus Motschulsky 被引量:7
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作者 TONG Jin , SUN Ji-yu , CHEN Dong-hui , ZHANG Shu-jun 1 1 1 2 1. Key Laboratory for Terrain-Machine Bionics Engineering (Ministry of Education, China), Jilin University, 5988 Renmin Street, Changchun 130022, P. R. China 2. Department of Multi-media and Computing, University of Gloucestershire, Cheltenham, The Park, GL50 2QF, UK. 1 《Journal of Bionic Engineering》 SCIE EI CSCD 2004年第4期221-230,共10页
The cuticle of dung beetle is a layered composite material in micro- or nano-scale. Dung beetle can fly, walk and dig. It can shovel and compact dung of mammals into balls. It use foreleg to walk, midleg and hindleg ... The cuticle of dung beetle is a layered composite material in micro- or nano-scale. Dung beetle can fly, walk and dig. It can shovel and compact dung of mammals into balls. It use foreleg to walk, midleg and hindleg to hold and impel dung ball. Its two foreleges as digging legs are developed. The factors impacting the nanoindentation testing results of the femur cuticle of forelegs of dung beetle Copris ochus Motschulsky were examined. The nanomechanical test instrument used for the tests was Hysitron nanomechanical system. The results shown that the holding time and loading time are important factors im- pacting the accuracy of such indentation properties as reduced modulus (Er) and the harness ( H ) of the femur cuticle of the forelegs of dung beetle Copris ochus Motschulsky in nanoscale. There exists a threshold holding time of 20 s for the reduced modulus of the femur cuticle. The tests of nanoindentation creep property and the regression analysis of relationship between the depth increment at the maximum load and the time further confirmed the correction of the above threshold holding time. There exist visco-elastic-plastic behaviour and creep phenomenon in the femur cuticle during indenting. Its creep property during the holding procedure at maximum load can be regressed by a general logarithmic equation. The equation fitted by the testing data is ? h = 54.83452 ln(0.00723t +1.00486), where, ? h is the depth increment at the maximum load and t is the time. 展开更多
关键词 INSECT dung beetle cuticle NANOINDENTATION holding time loading time creep 1
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Effects of shrub presence and shrub species on ground beetle assemblages (Carabidae,Curculionidae and Tenebrionidae) in a sandy desert,northwestern China 被引量:6
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作者 JiLiang LIU WenZhi ZHAO FengRui LI 《Journal of Arid Land》 SCIE CSCD 2015年第1期110-121,共12页
Shrub presence has an important effect on the structuring of ground beetles in desert ecosystems. In this study, in order to determine how shrubs and different species influence ground beetle assemblages in a sandy de... Shrub presence has an important effect on the structuring of ground beetles in desert ecosystems. In this study, in order to determine how shrubs and different species influence ground beetle assemblages in a sandy desert scrubland dominated by two different shrub species, namely Calligonum mongolicum and Nitraria sphaerocarpa, we sampled the ground beetles using pitfall traps during spring, summer and autumn in 2012. At the community level, the activity density of the ground beetles was shown to be significantly higher under shrubs than in intershrub bare habitats in spring; but an opposite pattern occurred in autumn, suggesting the presence of sea- son-specific shrub effects on the activity density of the ground beetles. Meanwhile, at the trophic group level, the activity density and species richness of predators were significantly greater under shrubs than in intershrub bare habitats in spring, whereas an opposite trend occurred on the activity density in autumn. N. sphaerocarpa shrubs had a positive effect on the activity density of herbivores in the three seasons, and C. mongolicum shrubs had a positive effect on the activity density of detritivores in spring and autumn. At the species level, more Microdera sp. was captured under shrubs than in intershrub bare habitats in spring. During the same time, we also found that C. mongolicum shrubs had a positive effect on Blaps gobiensis in spring, Carabus sp. in autumn, and Tentyria sp. in spring and autumn, and N. sphaerocarpa shrubs had a positive effect on Cyphogenia chinensis, Sternoplax setosa in spring and summer, and Curculionidae sp. 1 in summer and autumn. The study results suggest that shrub presence, shrub species and season variation are important factors for ground beetle assemblages in this desert ecosystem, but the responses of beetles differed among trophic and taxonomic levels. 展开更多
关键词 Calligonum mongolicum Nitraria sphaerocarpa ground beetle assemblages sandy desert ecosystem Heihe River basin
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Use of a Digital Image Correlation Technique for Measuring the Material Properties of Beetle Wing 被引量:4
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作者 Tailie Jin Nam Seo Goo +1 位作者 Sung-Choong Woo Hoon Cheol Park 《Journal of Bionic Engineering》 SCIE EI CSCD 2009年第3期224-231,共8页
Beetle wings are very specialized flight organs consisting of the veins and membranes.Therefore it is necessary from a bionic view to investigate the material properties of a beetle wing experimentally.In the present ... Beetle wings are very specialized flight organs consisting of the veins and membranes.Therefore it is necessary from a bionic view to investigate the material properties of a beetle wing experimentally.In the present study,we have used a Digital Image Correlation (DIC) technique to measure the elastic modulus of a beetle wing membrane.Specimens were prepared by carefully cutting a beetle hind wing into 3.0 mm by 7.0 mm segments (the gage length was 5 mm).We used a scanning electron microscope for a precise measurement of the thickness of the beetle wing membrane.The specimen was attached to a designed fixture to induce a uniform displacement by means of a micromanipulator.We used an ARAMISTM system based on the digital image correlation technique to measure the corresponding displacement of a specimen.The thickness of the beetle wing varied at different points of the membrane.The elastic modulus differed in relation to the membrane arrangement showing a structural anisotropy;the elastic modulus in the chordwise direction is approximately 2.65 GPa,which is three times larger than the elastic modulus in the spanwise direction of 0.84 GPa.As a result,the digital image correlation-based ARAMIS system was suc- cessfully used to measure the elastic modulus of a beetle wing.In addition to membrane's elastic modulus,we considered the Poisson's ratio of the membrane and measured the elastic modulus of a vein using an Instron universal tensile machine.The result reveals the Poisson's ratio is nearly zero and the elastic modulus of a vein is about 11 GPa. 展开更多
关键词 digital image correlation technique beetle wing elastic modulus Poisson's ratio VEIN MEMBRANE
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BAS-ADAM:An ADAM Based Approach to Improve the Performance of Beetle Antennae Search Optimizer 被引量:24
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作者 Ameer Hamza Khan Xinwei Cao +2 位作者 Shuai Li Vasilios N.Katsikis Liefa Liao 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第2期461-471,共11页
In this paper,we propose enhancements to Beetle Antennae search(BAS)algorithm,called BAS-ADAIVL to smoothen the convergence behavior and avoid trapping in localminima for a highly noin-convex objective function.We ach... In this paper,we propose enhancements to Beetle Antennae search(BAS)algorithm,called BAS-ADAIVL to smoothen the convergence behavior and avoid trapping in localminima for a highly noin-convex objective function.We achieve this by adaptively adjusting the step-size in each iteration using the adaptive moment estimation(ADAM)update rule.The proposed algorithm also increases the convergence rate in a narrow valley.A key feature of the ADAM update rule is the ability to adjust the step-size for each dimension separately instead of using the same step-size.Since ADAM is traditionally used with gradient-based optimization algorithms,therefore we first propose a gradient estimation model without the need to differentiate the objective function.Resultantly,it demonstrates excellent performance and fast convergence rate in searching for the optimum of noin-convex functions.The efficiency of the proposed algorithm was tested on three different benchmark problems,including the training of a high-dimensional neural network.The performance is compared with particle swarm optimizer(PSO)and the original BAS algorithm. 展开更多
关键词 Adaptive moment estimation(ADAM) beetle antennae search(BAM) gradient estimation metaheuristic optimization nature-inspired algorithms neural network
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基于Beetle微型控制器的多功能花卉传感器 被引量:1
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作者 樊星 马国祯 +1 位作者 邱雪莹 毛辰 《中国高新技术企业》 2016年第18期30-31,共2页
文章设计了一款多功能的花卉传感器,实现了对花卉生长环境的检测和状态反馈。系统可利用按键对花卉类型进行选择,通过多款传感器对花卉生长过程中的土壤湿度信息、温度信息和光照强度信息进行采集,并利用Beetle微型控制器进行数据处理,... 文章设计了一款多功能的花卉传感器,实现了对花卉生长环境的检测和状态反馈。系统可利用按键对花卉类型进行选择,通过多款传感器对花卉生长过程中的土壤湿度信息、温度信息和光照强度信息进行采集,并利用Beetle微型控制器进行数据处理,最后通过呼吸灯对状态进行反馈。 展开更多
关键词 beetle微型控制器 呼吸灯 昼夜平均 花卉传感器 花卉生长
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Investigation of beetle species that carry the pine wood nematode,Bursaphelenchus xylophilus(Steiner and Buhrer)Nickle,in China 被引量:8
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作者 Yang Wang Fengmao Chen +1 位作者 Lichao Wang Min Li 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第4期1745-1751,共7页
In order to found new carriers of pine wood nematode(PWN),Bursaphelenchus xylophilus,beetles were collected from pine wilt disease-affected areas in six provinces in China.A total of 8830 beetles of 29 species was col... In order to found new carriers of pine wood nematode(PWN),Bursaphelenchus xylophilus,beetles were collected from pine wilt disease-affected areas in six provinces in China.A total of 8830 beetles of 29 species was collected and examined to determine whether they were PWN carriers.Eight species were identified as carriers.Results included the first worldwide report of Monochamus uigromaculatus,Semanotus siuoauster,and Uraecha angusta being carriers of PWN,and the first report from China of A rhopalus rusticus carrying PWN.Monochamus alternatus was commonly collected in all six provinces and was the dominant species in four inland affected areas and A.rusticus was dominant in two coastal affected areas.The species varied between different neighboring regions in the same province.The distribution of the same species varied considerably over different regions. 展开更多
关键词 beetle CARRIER Pine wilt disease Pine wood nematode VECTOR
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Host selection behavior and incidence of the bark beetle Scolytus kashmirensis (Coleoptera:Curculionidae:Scolytinae) attacking elm (Ulmus spp.) trees in Kashmir 被引量:2
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作者 Abdul A.BUHROO 《Forestry Studies in China》 CAS 2012年第3期224-228,共5页
The status of the incidence of the bark beetle Scolytus kashmirensis Schedl on elm (Ulmus spp.) trees was determined in four districts of the Kashmir Valley in 2009. The incidence of the borer was higher in the Anan... The status of the incidence of the bark beetle Scolytus kashmirensis Schedl on elm (Ulmus spp.) trees was determined in four districts of the Kashmir Valley in 2009. The incidence of the borer was higher in the Anantnag (25.93%) and Shopian (22.35%) districts of the Kashmir Valley, followed by the Ganderbal (17.14%) and Baramulla (16.67%) districts. The overall infestation re- corded in these districts was 20.52%. The beetle under study chewed the scars on twigs of both the host and tentative non-host plants supplied to them in cages but bored and laid eggs in only one of them (the host plant). Both species of elm, Ulmus wallichiana and U. villosa, were susceptible to borer attacks; however, U. villosa showed low susceptibility and high resistance compared to U. wallichiana. Older, taller elms were preferred for feeding by bark beetles and are therefore much more susceptible to its infestation compared to younger elms. This bark beetle species also preferred to oviposit in branches of the host plants with diameters of 9-12 mm. 展开更多
关键词 bark beetle Ulmus spp. host selection INCIDENCE oviposition
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Genetic structure of the invasive Colorado potato beetle Leptinotarsa decemlineata populations in China 被引量:2
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作者 YANG Fang-yuan GUO Jian-jun +1 位作者 LIU Ning ZHANG Run-zhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第2期350-359,共10页
The Colorado potato beetle(CPB),Leptinotarsa decemlineata Say,is an infamous invasive species worldwide.It was first found in Xinjiang Uygur Autonomous Region of China in 1993 and spread to Northeast China in 2013.To ... The Colorado potato beetle(CPB),Leptinotarsa decemlineata Say,is an infamous invasive species worldwide.It was first found in Xinjiang Uygur Autonomous Region of China in 1993 and spread to Northeast China in 2013.To better understand the genetic structure and the diffusion path of their populations in China,we used nine polymorphic microsatellite loci to elucidate the genetic diversity,genetic structure and gene flow among nine CPB populations across Xinjiang and Northeast China.The results show that:(1)Two genetically separated clusters were identified by phylogenetic tree,principal coordinate analysis(PCoA)and Bayesian cluster method.Cluster one contained populations from Xinjiang,China.Cluster two contained populations from Northeast China.A genetic differentiation existed between the two clusters.(2)Three populations in Northeast China hold an obvious genetic differentiation according to the phylogenetic tree and PCoA,indicating that multiple introductions may occur in Northeast China.(3)The Altay population in Xinjiang showed a closer genetic relationship with the populations in Northeast China which may be due to the fact that they collectively originated in neighboring Russia.(4)Among all populations,Mulei and Wusu had obvious gene migrations from Tacheng,indicating that the inland populations are most likely to originate from Tacheng,Xinjiang. 展开更多
关键词 Colorado potato beetle genetic variation alien invasive species microsatellite marker
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基于Beetle Antennae Search算法主动配电网经济调度 被引量:4
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作者 于春庆 马睿 +1 位作者 徐建军 金凤楠 《吉林大学学报(信息科学版)》 CAS 2022年第4期608-615,共8页
为提高主动配电网的经济效益,在考虑分布式能源、网损费用和发电成本基础上,建立了主动配电网经济调度模型。模型加入了柔性软开关对主动配电网进行灵活调度和无功优化,使用优化后天牛须搜索算法对其进行求解,优化方法为在算法中加入遗... 为提高主动配电网的经济效益,在考虑分布式能源、网损费用和发电成本基础上,建立了主动配电网经济调度模型。模型加入了柔性软开关对主动配电网进行灵活调度和无功优化,使用优化后天牛须搜索算法对其进行求解,优化方法为在算法中加入遗传因子和锦标赛选择策略,使算法结果不会陷入局部最优,得到最小发电成本。最后经仿真实验,验证了优化后的天牛须搜索算法在主动配电网经济调度问题中具有实用性和高效性。 展开更多
关键词 主动配电网 天牛须搜索算法 经济调度 分布式电源
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Fault Diagnosis Based on BP Neural Network Optimized by Beetle Algorithm 被引量:7
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作者 Maohua Xiao Wei Zhang +2 位作者 Kai Wen Yue Zhu Yilidaer Yiliyasi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第6期252-261,共10页
In the process of Wavelet Analysis,only the low-frequency signals are re-decomposed,and the high-frequency signals are no longer decomposed,resulting in a decrease in frequency resolution with increasing frequency.The... In the process of Wavelet Analysis,only the low-frequency signals are re-decomposed,and the high-frequency signals are no longer decomposed,resulting in a decrease in frequency resolution with increasing frequency.Therefore,in this paper,firstly,Wavelet Packet Decomposition is used for feature extraction of vibration signals,which makes up for the shortcomings of Wavelet Analysis in extracting fault features of nonlinear vibration signals,and different energy values in different frequency bands are obtained by Wavelet Packet Decomposition.The features are visualized by the K-Means clustering method,and the results show that the extracted energy features can accurately distinguish the different states of the bearing.Then a fault diagnosis model based on BP Neural Network optimized by Beetle Algo-rithm is proposed to identify the bearing faults.Compared with the Particle Swarm Algorithm,Beetle Algorithm can quickly find the error extreme value,which greatly reduces the training time of the model.At last,two experiments are conducted,which show that the accuracy of the model can reach more than 95%,and the model has a certain anti-interference ability. 展开更多
关键词 Rolling bearing BP neural network beetle algorithm Wavelet packet transform
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Response of ground beetles(Coleoptera:Carabidae)to forest gaps formed by a typhoon in a red pine forest at Gwangneung Forest,Republic of Korea 被引量:1
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作者 Cheol Min Lee Tae-Sung Kwon Kwangil Cheon 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第1期173-181,共9页
In Korea, damaging typhoons related to climate change have increased steadily since the 1990s. Red pine (Pinus densiflora) forests in Gwangneung Forest were greatly disturbed by typhoon Kompasu in 2010. A survey was... In Korea, damaging typhoons related to climate change have increased steadily since the 1990s. Red pine (Pinus densiflora) forests in Gwangneung Forest were greatly disturbed by typhoon Kompasu in 2010. A survey was carried out to clarify differences in ground beetle (Coleoptera: Carabidae) communities between forest gaps and undamaged forests. Ground beetles were sampled using pitfall traps from early May to late October 2011. Vegetation changes, litter layer, organic matter layer, and soil conditions were also measured. A total of 1035 ground beetles of 32 species were collected. Contrary to our expectation, species richness, abundance, and community structure of the ground beetles in forest gaps were similar to those in undamaged forests. Species richness and abundance of habitat type were also similar. However, species diversity and estimated species richness in forest gaps were significantly higher than in undamaged forests. These findings suggest that forest gaps formed by a typhoon did not lead to great change in ground beetle communities. 展开更多
关键词 Climate change Ground beetle Forest gap Red pine forest TYPHOON
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Does variable stand structure associated with multi-cohort forests support diversity of ground beetle (Coleoptera, Carabidae) communities in the central Nearctic boreal forest? 被引量:1
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作者 Erica P. Barkley Jay R. Malcolm +1 位作者 Sandy M. Smith M. Isabel Bellocq 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第5期1191-1202,共12页
Multi-cohort management (MCM) that retains a range of stand structures (age and size class) has been proposed to emulate natural disturbance and improve management in the Nearctic boreal forest. Although MCM fores... Multi-cohort management (MCM) that retains a range of stand structures (age and size class) has been proposed to emulate natural disturbance and improve management in the Nearctic boreal forest. Although MCM forests contain both single- and multi-aged stands of mixed tree sizes, little is known about how variable stand structure affects associated fauna and biodiversity. Here, we examine the relationship between ground beetle (Coleoptera, Carabidae) communities and stand characteristics across a range of forest structure (=cohort classes). Given that MCM classes are defined by the distribution of their tree-stem diameters, we ask whether parameters associated with these distributions (Weibull) could explain observed variation in carabid communities, and if so, how this compares to traditional habitat variables such as stand age, foliage complexity or volume of downed woody debris. We sampled carabids using weekly pitfall collections and compared these with structural habitat variables across a range of cohort classes (stand structure and age since disturbance) in 18 sites of upland mixed boreal forests from central Canada. Results showed that richness and diversity of carabid communities were similar among cohort classes. Weibull parameters from the diameter distribution of all stems were the strongest predictors of variation in carabid communities among sites, but vertical foliage complexity, understory thickness, and percentage of deciduous composition were also significant. The abundance of several carabid forest specialists was strongly correlated with tree canopy height, the presence of large trees, and high vertical foliage complexity. Our results demonstrate that variable forest structure, as expected under MCM, may be useful in retaining the natural range of ground beetle species across the central Nearctic boreal forest. 展开更多
关键词 Biodiversity conservation Boreal forest CARABIDAE Forest structure Ground beetles Multi-cohortmanagement Tree diameter distribution
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