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ANALYSIS OF HABITAT PATTERN CHANGE OF RED-CROWNED CRANES IN THE LIAO HE DELTA USING SPATIAL DIVERSITY INDEX 被引量:3
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作者 WANGLing LIXiu-zhen +1 位作者 HUYuan-man GUODu-fa 《Chinese Geographical Science》 SCIE CSCD 2003年第2期164-170,共7页
Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. Th... Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. The result sho wed that the influence from human activities on the wetland habitat of red-crow ned cranes was prominent with the development of oil and agricultural exploitati on, and the habitat pattern of red-crowned cranes had been obviously changed by the human disturbance during the ten years. The areas with high Spatial Diversi ty values (SD≥0.65) and that with mid-high values (0.5≤SD< 0.65), which const ituted the main part of suitable habitat of red-crowned cranes,had reduced to 9142ha and 5576ha respectively, with the shrinking of natural land cover, such a s reed and Suaeda community. The habitat pattern became more fragmented, which w as caused by roads and wells during oil exploration. It was indicated that the s uitability and quality of habitat for red-crowned cranes in the Liaohe Delta we re degraded in the last decade. The results also showed that diversity index cou ld reflect the habitat suitability of red-crowned cranes quantitatively and des cribe the spatial pattern of the habitat explicitly. This study will provide a s cientific basis for habitat protection of red-crowned cranes and other rare spe cies in wetlands. 展开更多
关键词 spatial diversity Index red-crowned crane ( GrUS japonensis) habitatpattern the liaohe delta
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Habitat suitability change of red-crowned crane in Yellow River Delta Nature Reserve 被引量:2
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作者 CAO Ming-chang LIU Gao-huan 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第2期141-147,共7页
Habitat loss and fragmentation are mainly associated with population decrease of endangered species and biodiversity loss. The habitat suitability maps of red-crowned crane (Grusjaponensis) in 1992, 1999 and 2006 we... Habitat loss and fragmentation are mainly associated with population decrease of endangered species and biodiversity loss. The habitat suitability maps of red-crowned crane (Grusjaponensis) in 1992, 1999 and 2006 were produced by using Ecological Niche Suitability Model (ENSM) in Yellow River Delta Nature Reserve (118°33′-119°20′E longitude, 37°35′-38°12′N latitude), Shandong Province, China. Based on the habitat suitability maps, the causation and change law of habitat loss and fragmentation of red-crowned crane were analyzed by selecting a series of landscape pattern indices. Results showed that due to scarcities of fresh water sources, habitat suitability of red-crowned crane in 1999 was inferior to that in 1992 and 2006 no matter whether human disturbances existed or not. Besides, human disturbance activities, especially road disturbances, increased rapidly during the period of 1992-2006. This worsened the habitat loss and frag- mentation of red-crowned crane, and led to degrading habitat suitability of red-crowned crane in 2006, compared with that in 1992. In conclusion, fresh water sources and human disturbance activities are the two main factors that drive the habitat suitability change of red-crowned crane. 展开更多
关键词 red-crowned crane Yellow River Delta Nature Reserve habitat suitability habitat loss habitat fragmentation
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ANALYSIS OF THE ENVIRONMENT FEATURE OF BREEDING AREA AND ENDANGERED FACTORS OF RED-CROWNED CRANE IN CHINA 被引量:1
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作者 YU Jun-bao, LIU Jing-shuang, WANG Jin-da (Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021,P.R.China) 《Chinese Geographical Science》 SCIE CSCD 2001年第2期186-191,共6页
Red-crowned Crane (Grus japonensis), a kind of endangered large-scale wader, is one of valuable and rare birds in the world. It has been indexed in China Red Data Book of Endangered Animals (Aves), China Data Book of ... Red-crowned Crane (Grus japonensis), a kind of endangered large-scale wader, is one of valuable and rare birds in the world. It has been indexed in China Red Data Book of Endangered Animals (Aves), China Data Book of Major Protection Wild Animals, World Red Data Book of Birds, State Trade Protocol of Endangered Wild Plants and Animals Species. The paper studies the amount, distribution, habit, growth and habitat of Red-crowned Crane in China in detail, systematically analyses the ecological environment feature of Red-crowned Crane breeding area, including the vegetation feature, the vertical distribution law of absolute humidity and temperature, some carnivorous food and herbivorous food for Red-crowned Crane. At present, the ecological environment of breeding area has been destroyed seriously by human activity. The area of marshland is reduced rapidly. A large area of reeds has been disappeared. The survival of Red-crowned Crane is threatened greatly. So it′s necessary to maintain the biodiversity of breeding area in order to protect Red-crowned Crane. . 展开更多
关键词 red-crowned crane nature reserve CONSERVATION ENVIRONMENT
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Fecal DNA metabarcoding reveals the dietary composition of wintering Red-crowned Cranes(Grus japonensis) 被引量:1
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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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Suitable distance to observe Red-crowned Cranes:a note on the observer effect 被引量:4
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作者 李忠秋 《Chinese Birds》 2011年第3期147-151,共5页
In order to assess the effect of the observer distance on the behavior of Red-crowned Cranes (Grus japonensis),we studied their time budgets with a gradient of observer distances in Yancheng,China from December 2008 t... In order to assess the effect of the observer distance on the behavior of Red-crowned Cranes (Grus japonensis),we studied their time budgets with a gradient of observer distances in Yancheng,China from December 2008 to March 2009.Observer distance was classified into four levels,i.e.,< 200 m,200-300 m,300-400 m and > 400 m.The results indicated that cranes increased their vigilance when the observer was less than 300 m away.A safe distance for the observer was often as far as or more than 300 m.Cranes increased scan frequency when observers were within 200 m,whereas they prolonged the duration of their scan when observers were between 200 m and 300 m away,indicating two distinct vigilant strategies,given the observer distance.We suggest an observer distance of at least 300 m,in order to minimize the observer effect. 展开更多
关键词 crane observer distance observer effect VIGILANCE
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THE GROUND CENSUSES ON RED-CROWNED CRANE IN KHANKA LAKES DISTRICT OF CHINA
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作者 Piao RenzhuInstitute of Wildlife of Heilongjiang Province Sun Sen An Dongdong Northeast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1991年第2期83-88,共6页
Coordination of the aerial servey, the author carried ground census on the population size of Red-crowned crane(Grus japonensis) in Khanka Lakes District from 1984 to 1986. According to the census in spring of 1984, t... Coordination of the aerial servey, the author carried ground census on the population size of Red-crowned crane(Grus japonensis) in Khanka Lakes District from 1984 to 1986. According to the census in spring of 1984, the total number of Red-crowned crane is 72 individuals and 20 nests. So that this ground census has recorded 59 individuals more than the aerial survey of 13 individuals, and the percentage of nesting individuals in this flock is 55.6%, which is obviously higher than 36.9% of the average ratio in China. After this, in fall of 1984 and in spring of 1985 and 1986, we repeated the same censuses three times in the same districts, the results indicated that the flock of the crane in Khanka Lakes District is stable basically, but some individuals interchange with opposite flock of USSR because of gcgraphical adjoin.So, we believe this flock in China and that flock in USSR belong to the same population and suggest two countries should act in concert to studing on this population in future. Meanwhile, the aerial servey cooperate with ground census, it is the best way for reducing missing crane and achieving to high precision of census. From this, total number of Red-crowned crane in China is 542 individuals (483+59 ind ividuals). 展开更多
关键词 red-crowned crane Ground census Population size Khanka Lakes district
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Sex Identification of Red-crowned Crane by the Polymerase Chain Reaction
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作者 LIJian-hong LIShu-ling +1 位作者 BAOJun BAIXiu-juan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第2期151-155,共5页
Sex determining gene primers of Oriental White Stork were used to amplify sex-linked gene of the Red-crowned Crane′s W chromosome-specific by PCR for sex identification. The sexes of 7 couples of grown Red-crowned Cr... Sex determining gene primers of Oriental White Stork were used to amplify sex-linked gene of the Red-crowned Crane′s W chromosome-specific by PCR for sex identification. The sexes of 7 couples of grown Red-crowned Cranes and 15 youngs were identified. Through DNA sequence analysis, the identity is 94.77% between Red-crowned Crane and Oriental White Stork. The results of this study suggest that the application of the polymerase chain reaction technique is practicable for determining sex in the Red-crowned Crane. 展开更多
关键词 red-crowned crane sex determining gene sex identification
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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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Winter habitat selection of red-crowned crane (Grus japonensis)
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作者 张洪海 杨月伟 《Journal of Forestry Research》 CAS CSCD 2000年第1期44-46,共3页
This paper studied the winter habitat selection of red-crowned cranes (Grus japonensis) in Yancheng National Natural Reserve, Jiangsu Province. There were six types of habitat used by red-crowned cranes, i.e. salt-wor... This paper studied the winter habitat selection of red-crowned cranes (Grus japonensis) in Yancheng National Natural Reserve, Jiangsu Province. There were six types of habitat used by red-crowned cranes, i.e. salt-works, aquiculture ponds, reed lands, grassy tidal lands, salting wormwood lands and wheat fields. The wheat field was a new type of habitat used by red-crowned cranes. More than 70 percent of red-crowned cranes chose grassy tidal lands, salting wormwood lands, and reed lands as their most important habitats. In recent years, the distribution of red-crowned cranes moved southward gradually. Red-crowned cranes prefer artificial or semiartificial wetlands rather than original wetlands, successive distribution was broken into fragments. 展开更多
关键词 red-crowned craneS WINTER HABITAT HABITAT SELECTION
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Multi-scale analysis to uncover habitat use of red-crowned cranes: Implications for conservation 被引量:12
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作者 Chunyue LIU Hongxing JIANG +3 位作者 Shuqing ZHANG Chunrong LI Yunqiu HOU Fawen QIAN 《Current Zoology》 SCIE CAS CSCD 2013年第5期604-617,共14页
A multi-scale approach is essential to assess the factors that limit avian habitat use. Numerous studies have examined habitat use by the red-crowned crane, but integrated multi-scale habitat use information is lackin... A multi-scale approach is essential to assess the factors that limit avian habitat use. Numerous studies have examined habitat use by the red-crowned crane, but integrated multi-scale habitat use information is lacking. We evaluated the effects of several habitat variables quantified across many spatial scales on crane use and abundance in two periods (2000 and 2009) at Yancheng National Nature Reserve, China. The natural wetlands decreased in area by 30,601 ha (-6.9%) from 2000 to 2009, pre- dominantly as a result of conversion to aquaculture ponds and farmland, and the remaining was under degradation due to expan- sion of the exotic smooth cordgrass. The cranes are focusing in on either larger patches or those that are in close proximity to each other in both years, but occupied patches had smaller size, less proximity and more regular boundaries in 2009. At landscape scales, the area percentage of common seepweed, reed ponds and paddy fields had a greater positive impact on crane presence than the area percentage of aquaculture ponds. The cranes were more abundant in patches that had a greater percent area of common seepweed and reed ponds, while the percent area of paddy fields was inversely related to crane abundance in 2009 due to changing agricultural practices. In 2009, cranes tended to use less fragmented plots in natural wetlands and more fragmented plots in anthropogenic paddy fields, which were largely associated with the huge loss and degradation of natural habitats between the two years. Management should focus on restoration of large patches of natural wetlands, and formation of a relatively stable area of large paddy field and reed pond to mitigate the loss of natural wetlands [Current Zoology 59 (5): 604-617, 2013]. 展开更多
关键词 red-crowned crane Habitat Selection Remote sensing Scale PATCH LANDSCAPE
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Potential natural exposure of endangered red-crowned crane(Grus japonensis) to mycotoxins aflatoxin B_1, deoxynivalenol, zearalenone, T-2 toxin, and ochratoxin A 被引量:4
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作者 Da-wei LIU Hong-yi LIU +4 位作者 Hai-bin ZHANG Ming-chang CAO Yong SUN Wen-da WU Chang-hu LU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2016年第2期158-168,共11页
A survey was conducted to determine whether mycotoxins were present in the foods consumed by red-crowned cranes(Grus japonensis) in the Yancheng Biosphere Reserve, China. Collected in the reserve's core, buffer, an... A survey was conducted to determine whether mycotoxins were present in the foods consumed by red-crowned cranes(Grus japonensis) in the Yancheng Biosphere Reserve, China. Collected in the reserve's core, buffer, and experimental zones during overwintering periods of 2013 to 2015, a total of 113 food samples were analyzed for aflatoxin B1, deoxynivalenol, zearalenone, T-2 toxin, and ochratoxin A using high performance liquid chromatography(HPLC). The contamination incidences vary among different zones and the mycotoxins levels of different food samples also presented disparity. Average mycotoxin concentration from rice grain was greater than that from other food types. Among mycotoxin-positive samples, 59.3% were simultaneously contaminated with more than one toxin. This study demonstrated for the first time that red-crowned cranes were exposed to mycotoxins in the Yancheng Biosphere Reserve and suggested that artificial wetlands could not be considered good habitats for the birds in this reserve, especially rice fields. 展开更多
关键词 Food MYCOTOXIN red-crowned crane Yancheng Biosphere Reserve
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Impact of marsh changes on breeding cranes in Sanjiang Plain,northeastern China 被引量:1
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作者 江红星 钱法文 +5 位作者 刘春悦 李晓民 侯韵秋 张国钢 戴铭 刘冬平 《Chinese Birds》 2012年第3期165-179,共15页
In order to measure the impact of changes in the marsh on breeding Red-crowned Cranes (Grus japonensis) and White-naped Cranes (G.vipio) in the Sanjiang Plain,we conducted a complete crane súrvey in each of the s... In order to measure the impact of changes in the marsh on breeding Red-crowned Cranes (Grus japonensis) and White-naped Cranes (G.vipio) in the Sanjiang Plain,we conducted a complete crane súrvey in each of the summers of 2007 and 2008,and obtained information on the changes in its marsh through interpretation of satellite images in 1986,1995,2000 and 2005.A comparison between the 1984 and 2008 census shows that:1) the number of Red-crowned Cranes remained stable at about 300 birds,while the number of White-naped Cranes increased markedly; 2) the estimates of nests of Red-crowned cranes are close to the numbers of 1984,while approximately 90% of the nests of these two crane species were distributed over five national nature reserves (NNRs); 3) the two crane species became more concentrated in three regions,i.e.,the Fuyuan Delta,the middle reaches of the Naoli and Qixing rivers,and the Xingkai Lake wetlands,rather as formerly in six regions.The area of the marsh decreased by 45% within the 20-year period from 1986 to 2005.The major loss of the marsh area was in the form of a conversion to paddy fields and dry land,which can be primarily attributed to direct human activity under various economic and policy drivers.The disappearance of cranes in the Dulu and Abuqin rivers was induced by large-scale agricultural development.The fragmentation into and isolation of small areas of the marsh became increasingly more serious,which resulted in unsuitable condtions for crane breeding in small patches of the marsh.The number of cranes declined from 1984-1995 but had recovered remarkably by 2008,which may be due to theestablishment of a system of nature reserves,in place since 2000.The land ownership of the reserve plays a key role in maintaining the integrity of the wetland ecosystem,especially in Sanjiang,Honghe,Naolihe and Qixinghe NNRs,which together accommodated approximately 80% of the population of cranes.However,we did not discover any nests at all in the provincial and municipal reserves,which may be attributed to high human disturbances in these areas.In the end,we propose some recommendations on reserve management. 展开更多
关键词 red-crowned crane White-naped crane BREEDING population size marsh change habitat loss Sanjiang Plain
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Tower crane path planning based on improved ant colony algorithm
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作者 HE Yumin HU Xiangyang +3 位作者 ZHANG Jinhua YAO Shipeng LIU Difang MEN Xinyan 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第4期509-517,共9页
In order to solve the problem of path planning of tower cranes,an improved ant colony algorithm was proposed.Firstly,the tower crane was simplified into a three-degree-of-freedom mechanical arm,and the D-H motion mode... In order to solve the problem of path planning of tower cranes,an improved ant colony algorithm was proposed.Firstly,the tower crane was simplified into a three-degree-of-freedom mechanical arm,and the D-H motion model was established to solve the forward and inverse kinematic equations.Secondly,the traditional ant colony algorithm was improved.The heuristic function was improved by introducing the distance between the optional nodes and the target point into the function.Then the transition probability was improved by introducing the security factor of surrounding points into the transition probability.In addition,the local path chunking strategy was used to optimize the local multi-inflection path and reduce the local redundant inflection points.Finally,according to the position of the hook,the kinematic inversion of the tower crane was carried out,and the variables of each joint were obtained.More specifically,compared with the traditional ant colony algorithm,the simulation results showed that improved ant colony algorithm converged faster,shortened the optimal path length,and optimized the path quality in the simple and complex environment. 展开更多
关键词 tower crane ant colony algorithm transition probability local path chunking strategy path planning
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Evaluation of Driver-Induced Human Errors in Smart Construction Tower Crane Operations Based on DEMATEL-ISM-MICMAC
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作者 Jiahao Wang Wen Si 《Journal of Applied Mathematics and Physics》 2024年第4期1541-1556,共16页
With the advent of Industry 4.0, smart construction sites have seen significant development in China. However, accidents involving digitized tower cranes continue to be a persistent issue. Among the contributing facto... With the advent of Industry 4.0, smart construction sites have seen significant development in China. However, accidents involving digitized tower cranes continue to be a persistent issue. Among the contributing factors, human unsafe behavior stands out as a primary cause for these incidents. This study aims to assess the human reliability of tower crane operations on smart construction sites. To proactively enhance safety measures, the research employs text mining techniques (TF-IDF-Truncated SVD-Complement NB) to identify patterns of human errors among tower crane operators. Building upon the SHEL model, the study categorizes behavioral factors affecting human reliability in the man-machine interface, leading to the establishment of the Performance Shaping Factors (PSFs) system. Furthermore, the research constructs an error impact indicator system for the intelligent construction site tower crane operator interface. Using the DEMATEL method, it analyzes the significance of various factors influencing human errors in tower crane operations. Additionally, the ISM-MICMAC method is applied to unveil the hierarchical relationships and driving-dependent connections among these influencing factors. The findings indicate that personal state, operating procedures, and physical environment directly impact human errors, while personal capability, technological environment, and one fundamental organizational management factor contribute indirectly. . 展开更多
关键词 Text Mining DEMATEL-ISM-MICMAC Performance Shaping Factors Smart Construction Tower crane Operator
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一种随机应力谱在线分析方法及其在冶金起重机疲劳损伤分析中的应用
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作者 赵利强 饶培政 +3 位作者 丁克勤 陈力 郑惠泽 张理京 《北京化工大学学报(自然科学版)》 北大核心 2025年第1期83-92,共10页
冶金起重机工况复杂且长期连续进行吊装作业,其结构应力监测数据量大,连续周期长,使用常规的应力谱分析方法处理时会产生残波累积现象,导致结果准确性下降。针对此问题提出一种面向冶金起重机疲劳损伤评估的随机应力谱在线分析方法,首... 冶金起重机工况复杂且长期连续进行吊装作业,其结构应力监测数据量大,连续周期长,使用常规的应力谱分析方法处理时会产生残波累积现象,导致结果准确性下降。针对此问题提出一种面向冶金起重机疲劳损伤评估的随机应力谱在线分析方法,首先采用阶跃式雨流计数法对实时生成的随机应力数据进行分段计数并且实时输出随机应力谱,当循环分段计数产生的残波累积到一定程度时,对残波进行二次融合计数,并将此计数结果加入随机应力谱中修正实时计数结果,提升计数精度并用于后续的疲劳损伤评估。采用S-N曲线结合Miner损伤理论分析阶跃式雨流计数实时产生的应力谱并计算疲劳寿命,形成面向疲劳损伤评估的随机应力谱在线分析方法。分别采用四点雨流计数与阶跃式雨流计数对随机应力谱数据进行仿真实验,结果表明阶跃式雨流计数精度达到常规雨流计数的99%。使用该随机应力谱在线分析方法分析某冶金起重机副主梁连接处测点应力数据集并计算该测点处的有效疲劳寿命,结果证明该随机应力谱在线分析方法能够有效提升冶金起重机疲劳评估的实时性,评估结果合理,对起重机长期安全维护可提供及时有效的可靠依据。 展开更多
关键词 冶金起重机 疲劳评估 阶跃式雨流计数法 Miner疲劳理论 S-N曲线
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基于刚度折减法的岸边集装箱起重机结构损伤模拟
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作者 秦仙蓉 王令帅 +1 位作者 丁旭 杨穹 《起重运输机械》 2025年第1期38-44,共7页
岸边集装箱桥式起重机是码头集装箱进行装卸的专业设备,其前大梁、梯形架和拉杆往往受到交变载荷、冲击载荷,且在露天码头环境下受到锈蚀、涂膜剥离、裂纹等故障的侵袭,这会对其结构的刚度产生较大影响。鉴于此,文中以岸边集装箱起重机... 岸边集装箱桥式起重机是码头集装箱进行装卸的专业设备,其前大梁、梯形架和拉杆往往受到交变载荷、冲击载荷,且在露天码头环境下受到锈蚀、涂膜剥离、裂纹等故障的侵袭,这会对其结构的刚度产生较大影响。鉴于此,文中以岸边集装箱起重机为研究对象,提出了一种基于刚度折减法的岸边集装箱起重机损伤模拟方法 ,建立有限元模型对岸边集装箱起重机的前大梁、梯形架和拉杆分别进行损伤模拟,得到不同刚度折减程度下损伤状态的位移、应变等响应;同时,考虑到这3种损伤并不独立发生,采用正交试验方法基于该损伤模型对这3种损伤进行分组模拟,得到多损伤条件下的响应数据,从而进一步反映岸边集装箱起重机实际工况下的损伤规律。 展开更多
关键词 岸边集装箱起重机 刚度折减 损伤模拟 正交试验 结构分析
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Habitat utilization and resource partitioning of wintering Hooded Cranes and three goose species at Shengjin Lake 被引量:11
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作者 赵凤婷 周立志 徐文彬 《Chinese Birds》 CSCD 2013年第4期281-290,共10页
The loss and degradation of wetlands have adversely affected waterbirds, which depend on wetland habitats. Interspecific competition has an important effect on habitat utilization of wintering waterbirds. Resource uti... The loss and degradation of wetlands have adversely affected waterbirds, which depend on wetland habitats. Interspecific competition has an important effect on habitat utilization of wintering waterbirds. Resource utilization, including partitioning, in degraded wetlands has become a hot issue in ecological studies of wintering waterbirds. In order to have an insight into the habitat utilization and resource partitioning between a Hooded Crane(Grus monacha) population and the guild of three goose species, i.e., Anser fabalis, A. albifrons and A. erythropus wintering in lake wetlands, we carried out a study at Shengjin Lake National Nature Reserve from November 2011 to April 2012. We surveyed the Hooded Cranes and goose guild foraging in various habitats during the wintering periods with a combined method of fixed route searching and fixed site observations. Resource partitioning was studied by means of calculating habitat utilization rates and the width and overlap of spatial niches. The results showed that the habitat utilization rate and the width of spatial niches of the Hooded Crane population and goose guild shifted with the season. The habitat utilization rates of the cranes in grasslands were high at all three wintering stages. The habitat utilization rates were 0.454, 0.435 and 0.959 respectively for the Hooded Cranes and 0.627, 0.491 and 0.616 for the goose guild. This suggests that the overlap in grasslands was higher between cranes and goose guild. Most habitats were accessible at the middle stage, so the width of the spatial niche of the cranes(1.099) and goose guild(1.133) both reached their peak at this stage. The greatest niche overlap was 0.914 for these two groups at the late stage, followed by 0.906 at the middle stage and the smallest was 0.854 at the early stage. Ecological response to the changes in habitats of wintering waterbirds was clearly shown in the dynamic variations of the niche of both the Hooded Cranes and the three goose species. Coexistence among waterbirds was achieved by regulation of niche width to reduce niche overlap and relieve interspecific resource partitioning. 展开更多
关键词 habitat utilization NICHE wintering ecology Hooded crane(Grus monacha) goose guild
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Effects of human disturbance on the Hooded Crane (Grus monacha) at stopover sites in northeastern China 被引量:7
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作者 罗金明 王永洁 +1 位作者 杨帆 刘志军 《Chinese Birds》 2012年第3期206-216,共11页
There is a lack of information of whether the behavior pattern and physical condition of the Hooded Crane (Grus monacha) have been limited by conditions encountered at stopover sites in Changgou village,which is adjac... There is a lack of information of whether the behavior pattern and physical condition of the Hooded Crane (Grus monacha) have been limited by conditions encountered at stopover sites in Changgou village,which is adjacent to Zhalong Nature Reserve in northeastern China,one of the most important stopover sites of this crane.The objective of our research was to investigatethe impact of human-caused disturbances on the Hooded Cranes.We investigated three behavior activities of the Hooded Cranes,i.e.,flying time,flushing distance and the duration of vigilance.The results indicate that the auditory stimuli caused by local people provoked the most pronounced disturbances to the Hooded Crane.Human-caused disturbances not only frequently interrupt the feeding process of the cranes,but also lead to an increase of 200% in the duration of their vigilance and a significant increase in flying time from 0.4 to 0.7 h (p < 0.05).In addition,high-intensity noise can cause larger flushing distances; foraging cranes will flush away by about 600 m when disturbed by the honking of vehicles.Whistles or shouts by local farmers in the field generated the largest sound intensity,about 120 dB,which caused a flushing distance of over 700 m.In order to reduce the negative effect of human-caused disturbances on these cranes,it is imperative to define a buffer zone around sensitive areas during the fall stopover period.To solve the conflict between the interest of farmers and the demand for crops on the part of the cranes requires financial compensation to the farmers for the crops consumed by the Hooded Crane in order to enhance the conservation of this vulnerable bird species. 展开更多
关键词 migratory cranes foraging performance bahavior pattern flushing distance
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Fatigue behavior of crane beam strengthened with CFRP 被引量:2
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作者 石启印 李爱群 惠卓 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期561-565,共5页
In order to study the fatigue behavior of the damaged reinforced concrete (RC) beams strengthened by carbon fiber reinforced polymer (CFRP) laminate, three T-shaped beams strengthened by CFRP and one contrasting b... In order to study the fatigue behavior of the damaged reinforced concrete (RC) beams strengthened by carbon fiber reinforced polymer (CFRP) laminate, three T-shaped beams strengthened by CFRP and one contrasting beam are tested under fatigue loading, with the parameters of different modes of strengthening and different fatigue load levels considered. The main results obtained from the tests are: the width of the crack decreases 50. 2% to 66%, and the development of the crack is limited; the stress of steel decreases 24. 1% to 28. 2%, and the stiffness increases 14.9% to 16. 1% after being strengthened. Based on the technical specification for strengthening concrete structures with CFRP and the conclusions from the tests, a calculating scheme of the flexure stiffness is given, which can be used for reference in engineering design. Finally, some suggestions are given for design in fatigue strengthening. 展开更多
关键词 RC crane beam structure strengthening fatigue test carbon fiber reinforced polymer (CFRP)
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ROBOTIC DYNAMIC MODEL ON LOAD SWING OF SLEWING CRANE 被引量:1
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作者 王帮峰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期10-14,共5页
This paper sets up a robotic manipulator model on slewing crane. The model can synthetically describe the dynamic behavior of the load of slewing crane in rotating, elevating and hoisting motions. The dynamic equation... This paper sets up a robotic manipulator model on slewing crane. The model can synthetically describe the dynamic behavior of the load of slewing crane in rotating, elevating and hoisting motions. The dynamic equations of the system are recursively derived by a Newton Euler method. The dynamic behavior of the load of slewing crane in rotating motion is simulated on a computer. The method of robotic dynamics to derive the dynamic equations of the swing of load is accurate and convenient and it has good regularity. The result of the study provides a base in theory on design of crane and an accurate mathematical model for controlling the swing of load. 展开更多
关键词 ROBOT crane dynamics modeling swing of load computer simulation
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