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Fecal DNA metabarcoding reveals the dietary composition of wintering Red-crowned Cranes(Grus japonensis)
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作者 Hongyi Liu Wei Xu +6 位作者 Nan Xu Wenwen Zhang Haoming Jiang Yongqiang Zhao Changhu Lu Ying Zhu Peng Xu 《Avian Research》 SCIE CSCD 2023年第4期647-655,共9页
Understanding the diet of threatened wildlife is vital for species-specific conservation and habitat management measures.The Red-crowned Crane(Grus japonensis)is a vulnerable bird distributed in Northeast Asia.Previou... Understanding the diet of threatened wildlife is vital for species-specific conservation and habitat management measures.The Red-crowned Crane(Grus japonensis)is a vulnerable bird distributed in Northeast Asia.Previous dietary studies of this bird focused mainly on its plant food composition based on field observations and microhistological identification.Herein,a total of 45 fecal samples were collected in November,December and January(15 fecal samples each month)from wintering cranes,and then subjected to a high throughput sequencing meta-barcoding approach to determine the primary plant(rbcL)and animal(COI)food items in their diet.A total of 230 operational taxonomic units(OTUs)of plant foods and 371 OTUs of animal foods were obtained.The main plant foods in the wintering period were Miscanthus,Zea,and Hordeum genera,which were similar to those in the breeding and the migration periods.Both agricultural and natural plants were detected,indicating a relatively broad dietary niche for this crane species.However,the main animal foods were representatives of Theridiidae,Megascolecidae,and Agelenidae,in sharp contrast to previous studies.The higher number of small terrestrial arthropods in animal foods might be due to the indirect intake of plants.The composition of both plant and animal foods in the diet showed the highest diversity in December,while it was homogeneous in January.The plant of Zea genus became the main source of nutrition in late winter,as supplementary feeding was performed in the reserve,which could help Red-crowned Cranes to get through the cold season.The results obtained in this work would contribute to the development of effective conservation strategies for the Red-crowned Crane. 展开更多
关键词 Dietary composition Dietary niche Metabarcoding Molecular diet analysis Red-crowned Crane
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Annual spatio-temporal migration patterns of Hooded Cranes wintering in Izumi based on satellite tracking and their implications for conservation 被引量:2
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作者 Chunrong Mi Anders Pape Moller Yumin Guo 《Avian Research》 CSCD 2018年第3期264-272,共9页
Background: The Hooded Crane(Grus monacha) is listed as a vulnerable species by IUCN. Knowledge about the migration of the Hooded Crane is still limited. Here we reported the spatio-temporal migration patterns of Hood... Background: The Hooded Crane(Grus monacha) is listed as a vulnerable species by IUCN. Knowledge about the migration of the Hooded Crane is still limited. Here we reported the spatio-temporal migration patterns of Hooded Cranes wintering in Izumi, Japan, as well as important stopover areas for their conservation.Methods: Four adult and five subadult cranes, all wintering in Izumi, Japan, were fitted with satellite transmitters(GPS–GSM system) at their stopover sites in northeastern China in 2014 and 2015. We analyzed the time and duration of adults and subadults in spring and autumn migration, as well as the time and duration they stayed in breeding and wintering ground. In addition, we analyzed the land use of the cranes in stopover areas.Results: Adult cranes took much longer time to migrate both north in spring(mean days) compared with subadult cranes(15.3 and 5.2 days, respectively). H= 44.3 days) and south in fall(mean = 54.0 owever, the subadults had longer wintering(mean = 149.8 days) and nomadic(breeding season for adults) seasons(mean d with adults(133.8 and 122.3 days, respectively). Three important stopover areas have been= 196.8 days) compare identified: the region around Muraviovka Park in Russia, the Songnen Plain in China, and the west coast of South Korea, where cranes spent most of their migration time(62.2 and 85.7% in spring and autumn, respectively). During migration, nomadic period and winter, Hooded Cranes usually stay in croplands for resting and feeding. In non-wintering season, less than 6% of stopover sites were located within protected areas.Conclusion: Overall, our results contribute to understanding the annual spatio-temporal migration patterns of Hooded Cranes in the eastern flyway, and planning conservation measures for this species. 展开更多
关键词 CONSERVATION Eastern MIGRATION route Hooded cranes(Grus monacha) Izumi Satellite tracking SPATIOTEMPORAL MIGRATION patterns
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An Intelligent System for Real-Time Condition Monitoring of Tower Cranes 被引量:1
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作者 Aaron K. Adik Wilson Wang 《Intelligent Control and Automation》 2019年第4期155-167,共13页
Reliability and safety are major issues in tower crane applications. A new adaptive neurofuzzy system is developed in this work for real-time health condition monitoring of tower cranes, especially for hoist gearboxes... Reliability and safety are major issues in tower crane applications. A new adaptive neurofuzzy system is developed in this work for real-time health condition monitoring of tower cranes, especially for hoist gearboxes. Vibration signals are measured using a wireless smart sensor system. Fault detection is performed gear-by-gear in the gearbox. A new diagnostic classifier is proposed to integrate strengths of several signal processing techniques for fault detection. A hybrid machine learning method is proposed to facilitate implementation and improve training convergence. The effectiveness of the developed monitoring system is verified by experimental tests. 展开更多
关键词 Adaptive NEURO-FUZZY Systems MACHINE Learning DIAGNOSTICS PATTERN Classification TOWER cranes Smart Sensors
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Long-term monitoring data reveal effects of age,population density,and environmental aspects on hatching success of Common Cranes(Grus grus)
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作者 Isabel Barwisch Wolfgang Mewes Angela Schmitz Ornes 《Avian Research》 SCIE CSCD 2022年第3期347-355,共9页
Facing climate and land use change,a species’ability to successfully adapt to changing environments is crucial for its survival.Extensive drainage and intensification of agriculture and forestry set wetlands and asso... Facing climate and land use change,a species’ability to successfully adapt to changing environments is crucial for its survival.Extensive drainage and intensification of agriculture and forestry set wetlands and associated species at risk of population declines.The population of Common Cranes(Grus grus)has experienced considerable fluctuations over the last century.Despite increasing population numbers,hatching success seemed to have decreased over the last years.The aim of this study was to identify factors influencing hatching success and nest survival of Common Cranes based on analyses of long-term individual-based monitoring data from northeastern Germany and evaluate the species ability to adapt to changing environments.Hatching success decreased over the course of the study period from 0.75 to 0.55.Surprisingly,nest survival and hatching success did not vary across different nesting habitats,whereas factors such as female age,timing of nest initiation and breeding pair density were found to have significant effects on hatching success.Older females showed higher hatching success,even though the proportion of unhatched eggs was highest in females aged 20 years or older.Early nest initiation had a positive effect on hatching success.Water levels are more favorable early in the nesting season,whereas increasing evaporation with time causes water levels to decrease,granting easier access for predators.Independently of female age,hatching success decreased with increasing numbers of breeding pairs within a 2-km radius around a nesting site.High population densities intensify competition for resources and promote intraspecific interactions,affecting reproductive outcome negatively.This study gives first insights into mechanisms behind population regulation in Common Cranes,highlighting the importance of population dynamics and individual features.We suggest to further investigate density dependent effects including landscape and habitat features as well as reproductive success in terms of chick survival,since successfully raising juveniles is crucial for a species survival. 展开更多
关键词 ADAPTATION Age cranes Grus grus HABITAT Nest survival Population density REPRODUCTION
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Distribution of cranes in Hulunber Grassland and Daxing'an Mountains Forest Region in Inner Mongolia
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作者 王文 王秀辉 +1 位作者 高中信 印瑞学 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第1期55-58,共4页
The Daxing’an Mountains and Hulunber Grassland are located in the nor-theastern border area of China. This region covers a large area of rich biodiversity. The natural environment here is well protected because of Io... The Daxing’an Mountains and Hulunber Grassland are located in the nor-theastern border area of China. This region covers a large area of rich biodiversity. The natural environment here is well protected because of Iow pressure of human activity. There are 5 species of cranes here. They are Red-crowned crane (Grus japonensis), White-napped crane (Grus vipio), Siberian White crane (Grus leucogeranus), Grey crane (Grus lifordi) and Demoiselle crane (Anthropoides Virgo). Red-crowned crane is a breeding species that is widely distributed in this area. The main breeding population of this species is in Heilongjiang Province. They migrate to the south of China in winter. White-napped crane, Grey crane, Demoiselle crane are also summer birds. It remains unknown if Siberian White crane breeds here. Since the population of Red-crowned crane, White-napped crane, Siberian White crane in China are at the edge of endangering, so they are listed in the namelist of national protected species. But Grey crane, Demoiselle crane have a larger population. and are widely distributed. 展开更多
关键词 Hulunber GRASSLAND cranes HABITAT
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Sequential vigilance is unpredictable in reproductive Black-necked Cranes
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作者 Yuhang Li Le Yang +2 位作者 Yunchao Luo Yiqian Wu Zhongqiu Li 《Avian Research》 CSCD 2019年第1期82-88,共7页
Background:Vigilance refers to the behavior of animals scanning their surroundings with a main purpose of antipredation.Whether vigilance can serve the function of anti-predation depends on its unpredictability,meanin... Background:Vigilance refers to the behavior of animals scanning their surroundings with a main purpose of antipredation.Whether vigilance can serve the function of anti-predation depends on its unpredictability,meaning instantaneous randomness,sequential randomness,and independence,the three assumptions from Pulliam model(J Theor Biol 38:419,1973).Here we tested two of these three assumptions in reproductive Black-necked Cranes(Grus nigricollis) in Tibetan Plateau:instantaneous randomness and sequential randomness.Methods:Observations were carried out in July and September of 2014,July and August in 2017 in Selincuo National Nature Reserve,Tibet,with the help of focal sampling method.For instantaneous randomness,we used Kolmogorov–Smirnov test for its negative exponential distribution;for sequential randomness,we used Run test,correlation analysis,and generalized linear model to see if an inter-scan and its previous scan were correlated.Results:Not similar to some recent studies,we did not find a significant predictable vigilance in this crane.Most inter-scan intervals(86/100,86.0%) passed negative exponential distribution test,meaning vigilance sequences with instantaneous randomness;most inter-scan intervals(91/100,91.0%) passed sequential random test,showing vigilance sequences were random organized.Conclusion:Our results suggest that keeping a vigilance pattern with unpredictability is beneficial to the survival of the Black-necked Cranes,which are facing with both cruel natural environments and high predation risks. 展开更多
关键词 Black-necked cranes Instantaneous RANDOMNESS SEQUENTIAL RANDOMNESS
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Partnerships between the Managements of Cranes (<i>Grus grus</i>) and Kinneret Water Quality Protection in the Hula Valley, Israel
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作者 Moshe Gophen 《Open Journal of Modern Hydrology》 2017年第2期200-208,共9页
The historical habitat of swamps and a lake in the Hula Valley was modified during the early 1950’s. The Swamps and the old Hula Lake were drained and the land was converted to an agricultural development. As a resul... The historical habitat of swamps and a lake in the Hula Valley was modified during the early 1950’s. The Swamps and the old Hula Lake were drained and the land was converted to an agricultural development. As a result of inappropriate cultivation, it was necessary to once more implement management improvement. It was done within the Hula Project. Part of the Hula Project was a modified usage of 10% of the area previously used for agriculture for eco-tourism. Independently, thousands of migratory Cranes attracted by peanut crop leftover started wintering in the valley. These bird flocks significantly improved the management objective to ensure prevention of nutrient flux into Lake Kinneret. Consequently, the partnerships between Kinneret water quality protection, nature conservation and agricultural utilization of the peat land is presently operated. Migratory wintered Cranes is a factor of management stability accompanied by costly artificial feeding for bird in a dedicated land block to prevent damage to adjacent crops. 展开更多
关键词 cranes Hula Kinneret NUTRIENTS Water QUALITY
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Study on Integration Management and Control System of Port Cranes
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作者 Ping Deng Hanbin Xiao +1 位作者 Ying Zhu Shiqing Lu 《Intelligent Information Management》 2012年第3期80-84,共5页
This paper proposes the design scheme of Integration Management and Control System (IMCS) using the integration and optimization design theory of port cranes’ management and control system based on Enterprise Resourc... This paper proposes the design scheme of Integration Management and Control System (IMCS) using the integration and optimization design theory of port cranes’ management and control system based on Enterprise Resource Planning (ERP), Manufacturing Execution System (MES) and Process Control System (PCS). The functions, interface and software design of the three sub-modules of IMCS are presented. Outcomes of this research are being employed to practical port cranes’ operation and management, which eliminates the island phenomenon of cranes’ storage and application conditions between the management and control department. Hence, IMCS makes the integrated automatic port cranes system come true and it significantly improves the core competitiveness of the port. 展开更多
关键词 PORT cranes IMCS ERP MES PCS ISLAND Phenomenon
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Black-Necked Cranes is Tibet
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作者 DORMADORJE CUIFENG 《China's Tibet》 2002年第5期23-27,共5页
关键词 NATURE Black-Necked cranes is Tibet CR
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ZHUMO AND HER CRANES──Primitive Ecological Culture in ‘KingGesar’
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作者 DOLHA 《China's Tibet》 1999年第4期26-26,共1页
关键词 Primitive Ecological Culture in KingGesar ZHUMO AND HER cranes
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A Home for Cranes
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《China Today》 1998年第4期58-60,共3页
AHomeforCranesThankstoagroupofconcernedpeople,Chinaisprotectingitsbirds.WENBOCRANESinhabitopenmarshlands,wet... AHomeforCranesThankstoagroupofconcernedpeople,Chinaisprotectingitsbirds.WENBOCRANESinhabitopenmarshlands,wetplainsandprairies... 展开更多
关键词 A Home for cranes
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Variational analysis of mid-span deflection of gantry cranes 被引量:3
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作者 张大鹏 程文明 王彬 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第11期2705-2716,共12页
In practical application, it is very important to master the influence of structure parameters on the mid-span deflection quantificationally. For large-span and heavy-duty gantry cranes, the influence of the rigid leg... In practical application, it is very important to master the influence of structure parameters on the mid-span deflection quantificationally. For large-span and heavy-duty gantry cranes, the influence of the rigid leg and the soft leg on mid-span deflection has not been considered in the past. In the paper, the mathematical model is established for universal large-span and heavy-duty gantry cranes. The analytical solution for the mid-span deflection of gantry-frame structure girder is derived and obtained based on the variation principle by considering the coupling effect of the bending moments of girder and legs, the axial force and the secondary bending moments. The relation between the load and the deflection on the mid-span of the gantry-frame structure girder is known. Then, the experimental model is designed according to dimensional analysis method. And experiments were performed on the WEW-600 B type testing machine. Hackling experimental data, the regular of the load and deflection on the girder mid-span is obtained, namely, the deformation of the gantry-frame structure resists the external load to do work. The validity of the nonlinear analytical solution of the girder deflection is verified. Experimental results show that the analytical solution of the gantry-frame structure deflection has much higher calculation accuracy than previous calculation method. This work provides a theoretical basis for the design and inspection of gantry-frame structures. 展开更多
关键词 GANTRY CRANE DEFLECTION STRUCTURAL STIFFNESS VARIATIONAL analysis
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Load Reduction Test Method of Similarity Theory and BP Neural Networks of Large Cranes 被引量:4
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作者 YANG Ruigang DUAN Zhibin +2 位作者 LU Yi WANG Lei XU Gening 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第1期145-151,共7页
Static load tests are an important means of supervising and detecting a crane's lift capacity. Due to space restrictions, however, there are difficulties and potential danger when testing large bridge cranes. To solv... Static load tests are an important means of supervising and detecting a crane's lift capacity. Due to space restrictions, however, there are difficulties and potential danger when testing large bridge cranes. To solve the loading problems of large-tonnage cranes during testing, an equivalency test is proposed based on the similarity theory and BP neural networks. The maximum stress and displacement of a large bridge crane is tested in small loads, combined with the training neural network of a similar structure crane through stress and displacement data which is collected by a physics simulation progressively loaded to a static load test load within the material scope of work. The maximum stress and displacement of a crane under a static load test load can be predicted through the relationship of stress, displacement, and load. By measuring the stress and displacement of small tonnage weights, the stress and displacement of large loads can be predicted, such as the maximum load capacity, which is 1.25 times the rated capacity. Experimental study shows that the load reduction test method can reflect the lift capacity of large bridge cranes. The load shedding predictive analysis for Sanxia 1200 t bridge crane test data indicates that when the load is 1.25 times the rated lifting capacity, the predicted displacement and actual displacement error is zero. The method solves the problem that lifting capacities are difficult to obtain and testing accidents are easily possible when 1.25 times related weight loads are tested for large tonnage cranes. 展开更多
关键词 similarity theory BP neural network large bridge crane load reduction equivalent test method
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Effects of variation in food resources on foraging habitat use by wintering Hooded Cranes(Grus monacha) 被引量:8
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作者 Meng Zheng Lizhi Zhou +1 位作者 Niannian Zhao Wenbin Xu 《Chinese Birds》 CSCD 2015年第3期186-195,共10页
Background:The ideal habitat use of waterbirds can be considered to be fixed,but current habitat use depends on environmental conditions,especially those of food characteristics,considered crucial to their use of habi... Background:The ideal habitat use of waterbirds can be considered to be fixed,but current habitat use depends on environmental conditions,especially those of food characteristics,considered crucial to their use of habitats.Understanding how waterbirds respond to variation in food availability at degraded wetland sites and change their habitat use patterns over spatial and temporal scales should direct future conservation planning.The objectives of this study were to identify these spatial-temporal foraging habitat use patterns of Hooded Cranes(Grus monacha)and their relationship with food characteristics in the severely degraded wetlands of the Shengjin and Caizi lakes along with the Yangtze River floodplain.Methods:We investigated the changes in food characteristics,relative abundance and density of Hooded Cranes in various habitat types across three winter periods from November 2012 to April 2013.We examined the effect of these winter periods and habitat types on the pattern of use by the cranes and explored the relationship between these patterns and food characteristics using linear regression.Results:The food characteristics and habitat use clearly changed over spatial-temporal scales.In the early and mid-winter periods,the most abundant,accessible and frequented food resources were found in paddy fields,while in the late period the more abundant food were available in meadows,which then replaced the paddy fields.There were fewer effects of winter periods,habitat types and their interactions on habitat use patterns except for the effect of habitat types on the relative abundance,determined as a function of food abundance,but independent of food depth and sediment permeability.Conclusions:In response to the degradation and loss of lake wetlands,the cranes shifted their habitat use patterns by making tradeoffs between food abundance and accessibility over spatial-temporal scales that facilitated their survival in the mosaic of these lake wetlands. 展开更多
关键词 Hooded Crane(Grus monacha) HABITAT use Food characteristics WINTERING ECOLOGY FORAGING HABITAT
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Foraging habitat selection of overwintering Black-necked Cranes in the farming area surrounding the Caohai Wetland, Guizhou Province, China 被引量:4
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作者 Dawei Wu Canshi Hu +2 位作者 Mingming Zhang Zhumei Li Haijun Su 《Avian Research》 CSCD 2020年第1期74-82,共9页
Background: Understanding how overwintering birds choose foraging habitats is very important for conservation management. The overwintering Black-necked Crane(Grus nigricollis) feeds on crop remains in farmlands;thus,... Background: Understanding how overwintering birds choose foraging habitats is very important for conservation management. The overwintering Black-necked Crane(Grus nigricollis) feeds on crop remains in farmlands;thus, reasonable conservation management of this type of farmland that surrounds wetlands is critical for the overwintering populations of the Black-necked Crane;however, it is not clear how the Black-necked Crane chooses the foraging land in the farmland.Methods: A thorough field positioning survey of all foraging sites in farmland areas around the Caohai Wetland and a-sampling analysis of habitat selection by the Black-necked Crane were conducted during the winters from 20162017 and 2017-2018.Results: Multiple factors contributed to the selection of foraging habitat in farmlands, i.e., food factors(crop remains and tillage methods) > human disturbance factors(distance to road and settlement) > topography factors(slope aspect), listed according to the strength of influence. Additionally, Black-necked Cranes tend to choose farmland sites where there was no machine tillage, the crop remains were > 500 g/m^2, the distance to residences ranged from 100 to 500 m, the distance to roads ranged from 50 to 100 m, and the slopes exhibited western or eastern aspects. As the winters progressed, the volume of the edible crop remains declined, and the influences of the other main factors also changed, i.e., the factors of human disturbance(distance to road and settlement) became less important, while the effect of the food factor(crop remains) was strengthened. Thus, the foraging sites near the road became more important.Conclusion: The farming area surrounding the Caohai Wetland is very important for the overwintering Black-necked Crane. Food factors and human disturbance factors are the main factors that influence the choice of feeding ground. 展开更多
关键词 Black-necked Crane Caohai WETLAND in Guizhou FARMLAND around the WETLAND FORAGING habitat SELECTION OVERWINTERING period
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Review of Antiswing Control of Shipboard Cranes 被引量:3
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作者 Yuchi Cao Tieshan Li 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第2期346-354,共9页
Shipboard cranes are extensively utilized in numerous fields such as cargo transferring and offshore engineering.The control of shipboard cranes,especially the antiswing control of payloads,has attracted much research... Shipboard cranes are extensively utilized in numerous fields such as cargo transferring and offshore engineering.The control of shipboard cranes,especially the antiswing control of payloads,has attracted much research attention due to their typical underactuation characteristics and complicated dynamics.Through comparisons of the traditional land-fixed cranes,a brief review on modeling and dynamics analysis is presented to illustrate the tremendous challenges and difficulties in controller design for shipboard cranes.A comprehensive review and brief analysis of shipboard crane control strategies are further presented.Some future research directions are also put forward for reference.It is expected that the paper will be useful for improving existing control schemes and generating novel control approaches for shipboard crane systems. 展开更多
关键词 Control review shipboard crane underactuated system
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3D Digital Design of Cranes' Structures Based on Hybrid Software Architecture 被引量:1
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作者 WANG Chonghua1,LI Hua 1,2 (1.Dept. of Mechanical Engineering,Shanghai Maritime University,Shanghai 200135,China 2.Worcester Polytechnic Institute,Worcester 01609,MA,USA) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S1期96-101,共6页
3D digital design for cranes’ structures based on hybrid software architecture of Client/Server and Browser/Server is introduced in this paper. Based on Pro/ENGINEER platform,3D parametric model family is built to al... 3D digital design for cranes’ structures based on hybrid software architecture of Client/Server and Browser/Server is introduced in this paper. Based on Pro/ENGINEER platform,3D parametric model family is built to allow generation of feasible configurations of cranes’ structures in Client/Server framework. Taking use of Visual C++,the second exploiting software kit provided by Pro/ENGINEER and ANSYS GUI/APDL modeling patterns,an integration method of 3D CAD and CAE is achieved,which includes regeneration of 3D parametric model,synchronous updating and analysis of FEA model. As in Browser/Server framework,the 3D CAD models of parts,components and the whole structure could also be displayed in the customer’s browser in VRML format. 展开更多
关键词 digital design crane’s structure HYBRID SOFTWARE architecture CAD/CAE integration
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Shifts in foraging behavior of wintering Hooded Cranes(Grus monacha) in three different habitats at Shengjin Lake, China 被引量:2
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作者 Wenjing Wan Lizhi Zhou Yunwei Song 《Chinese Birds》 CSCD 2016年第3期167-173,共7页
Background: Wetland loss and degradation result in a reduction in the availability and quality of food for wintering waterbirds. Birds normally modify their foraging behavior to adapt to variations in food availabilit... Background: Wetland loss and degradation result in a reduction in the availability and quality of food for wintering waterbirds. Birds normally modify their foraging behavior to adapt to variations in food availability. In this study, we compared shifts in foraging behavior of Hooded Cranes(Grus monacha) in three different habitats at Shengjin Lake, China to understand the response of these cranes to changes in habitat.Methods: We investigated the food density and foraging behavior of Hooded Cranes in Shengjin Lake National Nature Reserve from November 2014 to April 2015. We used regression equations to describe the changes in food density. A total of 397 behavioral observations were used in the analyses of their foraging efforts. We fitted a candidate set of generalized mixed linear models to analyze the relationship of foraging efforts and food density. We used a method of information theory to guide the selection of the model and Akaike's Information Criterion to calculate the value of each model. The relationship between food density, disturbances and foraging behavior was illustrated using a generalized linear model.Results: Along with the temporal variation and exploitation of food biomass, the food density varied widely among foraging sites. During the early winter period, foraging efforts were more pronounced in the paddy fields and meadows but not significantly different among the three habitats. The cranes spent more foraging effort in the paddy fields and meadows during the middle stage and in the meadows and mudflats during the late winter. The results of the generalized linear model showed that food density and disturbances had different effects on the rate of foraging success during the winter, while the effect of foraging effort was not significant. Furthermore, the rate of feeding success was markedly affected by disturbances in the paddy fields. The combined action of food density and disturbances had a significant effect on the rate of foraging success in the meadows, while the effect of foraging effort was also not significant in three habitats.Conclusions: Changes in foraging behavior were significant in three habitats, which were affected by food density and disturbances. The rate of foraging success increased in the habitat with low food density and low disturbances to increase the foraging efficiency in the lake. With abundant food and a high level of disturbance, the rate of foraging success decreased to ensure more secure access to food. 展开更多
关键词 Food density Foraging behavior Habitat quality Hooded Crane
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HYBRID CONTROL APPROACH FOR CONTAINER CRANES 被引量:4
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作者 Wang Xiaojun Shao Huihe 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期351-355,共5页
A hybrid control approach is proposed to achieve the desired performance. Firstly a robust input shaper is designed to reduce the transient vibration and residual vibration of the container efficiently. Then a simple ... A hybrid control approach is proposed to achieve the desired performance. Firstly a robust input shaper is designed to reduce the transient vibration and residual vibration of the container efficiently. Then a simple fuzzy logic controller is designed to eliminate the residual vibration completely in order to guarantee the positioning precision. Such a hybrid approach is simple in structure and readily realizable. Simulation results verify the fine performance of this hybrid control approach. It can achieve perfect elimination of residual vibration and concise positioning of the container load, and it is robust to parameter variations (mainly for cable length) and external disturbances. 展开更多
关键词 Input shaping Fuzzy logic control Container crane Vibration
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A growing captive population erodes the wild Red-crowned Cranes(Grus japonensis) in China 被引量:1
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作者 Daqing Zhou Xin Xia +5 位作者 Wanggu Xu Haonan Zhang Zhedong Qian Jun Gao Zhi Wang Mingkang Jiang 《Chinese Birds》 CSCD 2016年第4期210-217,共8页
Background: The Red-crowned Crane(Grus japonensis) is an endangered bird species and while the wild population continues to decrease in China, the captive population has dramatically increased over the last two decade... Background: The Red-crowned Crane(Grus japonensis) is an endangered bird species and while the wild population continues to decrease in China, the captive population has dramatically increased over the last two decades. We hypothesized that some of the captive Red-crowned Cranes originated from the wild and that a growing captive population is eroding the wild population in China.Methods: We surveyed the size of the population and determined the average annual growth rate, reproductive success rate and mortality rate of captive Red-crowned Cranes in 2013 in China. We assessed this erosion effect through mathematical models, in which the size of the captive Red-crowned Crane population was determined from the annual growth rate, the reproductive success rate and the rate of mortality.Results: We found there were a total of 1520 captive Red-crowned Cranes in 2013 in China, with an average annual gro-wth rate of 7.46%, a reproductive success rate of 9.17% and a mortality rate of 3.6%. We found that approximately 1027 supplementary Red-crowned Cranes per year and a total of 244, over the 14 year period from 1999 to 2013, were needed to account for the growing captive population in China.Conclusion: We conclude that the 244 birds probably came from the wild by taking eggs and capturing juveniles or adults and hence accepted the hypothesis. Perhaps more surprisingly, our annual estimate of the number of supplementary Red-crowned Cranes in captive populations is very conservative, with the erosion effect substantially underestimated, because the total number of captive Red-crowned Cranes in 2013 was underestimated, with the annual reproductive success rate in zoos overestimated. The existence of an erosion effect provides a new perspective for the interpretation of why the Red-crowned Crane population in the wild continues to decrease. In our opinion, it is important to understand the consequences of this erosion effect on the management and conservation of this endangered bird species in China. 展开更多
关键词 ZOO Nature reserve CRANE Captive population Reproductive success rate
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