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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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Effects of diet shift on the gut microbiota of the critically endangered Siberian Crane 被引量:1
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作者 Wenjuan Wang Yafang Wang +1 位作者 Qing Chen Huifang Ding 《Avian Research》 SCIE CSCD 2023年第3期443-452,共10页
Wetlands worldwide have suffered from serious degradation and transformation,leading to waterbirds increasingly dependent on agricultural fields for feeding.Although gut microbiota is an essential component of host he... Wetlands worldwide have suffered from serious degradation and transformation,leading to waterbirds increasingly dependent on agricultural fields for feeding.Although gut microbiota is an essential component of host health,the impacts of agricultural feeding on gut microbial community and pathogen transmission remain poorly understood.To fill this knowledge gap,we used 16S rRNA sequencing to characterize the fecal bacterial community of the Siberian Crane(Grus leucogeranus),a Critically Endangered species,that recently has shifted its foraging from largely Vallisneria tubers in Poyang Lake natural wetlands to crops(i.e.,rice seeds and lotus rhizomes) in agricultural fields.We compared the bacterial communities between tuber foraging cranes and crop foraging cranes.Our results indicate that diet shift greatly modified the gut microbiota diversity,composition and function.Crop foraging cranes had higher microbiota diversity than tuber foraging cranes.The alteration in microbiota composition and function were correlated with change in food nutrition.Tuber(i.e.,high in fiber)foraging cranes were enriched in Clostridiaceae with fiber digestion ability,and crop(i.e.,high in carbohydrate)foraging cranes were enriched in bacterial taxa and functions related to carbohydrate metabolism.The flexibility of gut microbiota might enhance Siberian Cranes’ ability to adapt to novel diet and environment.However,many enriched families in crop foraging cranes were pathogenic bacteria,which might increase the susceptibility of cranes to pathogenic infection.Special caution should be taken to agricultural feeding waterbirds in Asia,where the widespread poultry-keeping in over-harvested rice fields might increase the transmission probability of pathogenetic bacteria among wild birds,domestic poultry and humans. 展开更多
关键词 Diet shift Pathogenic bacteria Poyang Lake Siberian crane Vallisneria tuber Wetland degradation
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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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Rehabilitation of Overhead Crane in HPP
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作者 Nannan Qu Yonggang Si +2 位作者 Fupeng Zheng Zhi Chen Jiuqiang Huang 《Modern Electronic Technology》 2023年第2期7-12,共6页
This paper presents a case study on the repair of a mechanical component of an overhead crane.The problem was initially identified through on-site inspection and analysis of the crane’s performance.The mechanical par... This paper presents a case study on the repair of a mechanical component of an overhead crane.The problem was initially identified through on-site inspection and analysis of the crane’s performance.The mechanical part was found damaged,leading to safety concerns and operational inefficiencies.The paper details the process of diagnosing the issue,developing a repair plan,and executing the repair work.The repair plan involved replacing the damaged component with a new one and conducting additional maintenance work to ensure optimal performance.The paper also discusses the outcomes of the repair work,which led to improved safety and increased efficiency of the overhead crane.The case study provides insights into the importance of regular maintenance and on-site inspections in ensuring the safe and efficient operation of mechanical systems. 展开更多
关键词 Mechanical component Overhead crane Operational inefficiencies
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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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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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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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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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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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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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Status and behavior of the Black-necked Crane (Grus nigricollis) in the Altun Mountain Reserve,Xinjiang
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作者 张同 马鸣 +2 位作者 丁鹏 徐峰 Paul J.BUZZARD 《Chinese Birds》 2012年第3期199-205,共7页
The Black-necked Crane (Grus nigricollis) is an endemic species of the Qinghai-Tibetan Plateau,with its population in Xinjiang largely found in the Kunlun and Altun mountain regions.A survey of the distribution,popula... The Black-necked Crane (Grus nigricollis) is an endemic species of the Qinghai-Tibetan Plateau,with its population in Xinjiang largely found in the Kunlun and Altun mountain regions.A survey of the distribution,population dynamics,flock size and behavior was conducted in Altun Mountain National Natural Reserve from September to November 2011.We investigated the size and distribution of its population in this area with a sample spot survey and by direct counting.We found Black-necked Cranes on the wetlands of Wuzunxiaoer,Yusup Aleksei,Yaziquan,Qimantag,Tula Ranch and elsewhere,where we recorded 126 individual birds of the species in Yixiekepati (37° 15′-37°23′N,90°11′-90°20′E,elevation 3903 m),the largest population we have observed in this area.In the reserve,the population consists of about 180-200 birds.Combined with previous records,we conclude that more than 260 Black-necked Cranes live in Xinjiang.Cranes gathered conspicuously in the middle of October where the highest number of birds appeared on 29 October.All of the cranes had migrated out of this area by 6 November.Time budgets and diurnal behavior rhythms of Blacknecked Cranes were observed in the Yixiekepati wetland at daylight (from 06:00 to 18:00).Foraging was the most prevalent type of behavior during the autumn period,accounting for 58.9% of the diurnal time budget,followed by preening (13.2%),vigilance (9.5%),walking (8.2%),flying (3.5%),resting (3.4%),chirping (2.7%) and other types of behavior (0.6%). 展开更多
关键词 Black-necked crane Grus nigricollis distribution population size behavior rhythm XINJIANG
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On Naturalism in Stephen Crane's The Open Boat
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作者 王秀红 陈贝贝 《海外英语》 2014年第17期212-217,共6页
Stephen Crane is one of the greatest figures in the history of American literature and his novella The Open Boat is widely known by people all over the world as a representative work of Naturalism. This paper aims at ... Stephen Crane is one of the greatest figures in the history of American literature and his novella The Open Boat is widely known by people all over the world as a representative work of Naturalism. This paper aims at exploring Naturalism in Stephen Crane's The Open Boat,which will guide the readers to understand American Naturalism accurately and thoroughly. It firstly introduces the author and his novel The Open Boat. Secondly,it progressively dissects Naturalism. It not only analyses the general characteristics of Naturalism with details in The Open Boat,but also interprets the distinguishing features of American Naturalism so that readers can better understand the features of American Naturalism. Through textual perusal,it further studies the unique characteristics of Stephen Crane's Naturalism and lays particular emphasis on Crane's special concern on the awakening of humanity. It is hoped that this thesis can help readers get an in-depth comprehension of Naturalism and gain some inspiration from TheOpenBoat. 展开更多
关键词 NATURALISM Stephen crane the OPEN BOAT
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Pendulation reduction on ship-mounted container crane via T-S fuzzy model 被引量:9
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作者 JANG Jae Hoon KWON Sung-Ha JEUNG Eun Tae 《Journal of Central South University》 SCIE EI CAS 2012年第1期163-167,共5页
Ship-mounted container cranes are challenging industrial applications of nonlinear pendulum-like systems with oscillating disturbance which can cause them unstable.Since wave-induced ship motion causes the hoisted con... Ship-mounted container cranes are challenging industrial applications of nonlinear pendulum-like systems with oscillating disturbance which can cause them unstable.Since wave-induced ship motion causes the hoisted container to swing during the transfer operation,the swing motion may be dangerously large and the operation must be stopped.In order to reduce payload pendulation of ship-mounted crane,nonlinear dynamics of ship-mounted crane is derived and a control method using T-S fuzzy model is proposed.Simulation results are given to illustrate the validity of the proposed design method and pendulation of ship-mounted crane is reduced significantly. 展开更多
关键词 ship-mounted crane DISTURBANCE pendulation control T-S fuzzy model
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Design for a Crane Metallic Structure Based on Imperialist Competitive Algorithm and Inverse Reliability Strategy 被引量:6
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作者 Xiao-Ning Fan Bo Zhi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期900-912,共13页
Uncertainties in parameters such as materials, loading, and geometry are inevitable in designing metallic structures for cranes. When considering these uncertainty factors, reliability-based design optimization (RBDO... Uncertainties in parameters such as materials, loading, and geometry are inevitable in designing metallic structures for cranes. When considering these uncertainty factors, reliability-based design optimization (RBDO) offers a more reasonable design approach. However, existing RBDO methods for crane metallic structures are prone to low convergence speed and high computational cost. A unilevel RBDO method, combining a discrete imperialist competitive algorithm with an inverse reliabil- ity strategy based on the performance measure approach, is developed. Application of the imperialist competitive algorithm at the optimization level significantly improves the convergence speed of this RBDO method. At the reli- ability analysis level, the inverse reliability strategy is used to determine the feasibility of each probabilistic constraint at each design point by calculating its a-percentile per- formance, thereby avoiding convergence failure, calcula- tion error, and disproportionate computational effort encountered using conventional moment and simulation methods. Application of the RBDO method to an actual crane structure shows that the developed RBDO realizes a design with the best tradeoff between economy and safety together with about one-third of the convergence speed and the computational cost of the existing method. This paper provides a scientific and effective design approach for the design of metallic structures of cranes. 展开更多
关键词 crane metallic structure Reliability-baseddesign optimization Imperialist competitive algorithmPerformance measure approach Inverse reliabilitystrategy
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The effects of food abundance and disturbance on foraging flock patterns of the wintering Hooded Crane(Grus monacha) 被引量:9
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作者 Ling Yang Lizhi Zhou Yunwei Song 《Chinese Birds》 CSCD 2015年第3期178-185,共8页
Background:Food abundance and availability affect flock patterns of foraging birds.Cost and risk tradeoffs are especially critical for flocks of wintering waterbirds foraging in lake wetlands.Waterbirds losing suitabl... Background:Food abundance and availability affect flock patterns of foraging birds.Cost and risk tradeoffs are especially critical for flocks of wintering waterbirds foraging in lake wetlands.Waterbirds losing suitable habitats face insufficient food supplies and high levels of disturbance,affecting their foraging activities.Our objective was to study the effects of food abundance and disturbances on flock size and the structure of Hooded Crane flocks wintering at Shengjin Lake and,as well,to understand the response of wintering waterbirds to habitat degradation for future management decisions and protection of the population.Methods:We investigated food abundance,disturbances and flock foraging activities of the wintering Hooded Crane in several foraging habitats of Shengjin Lake from November 2013 to April 2014.Flock size and structure were observed by scan sampling.Data on food abundance and disturbances were collected by sampling.Flock size and structure were compared among three wintering stages.The relationship between food resources,disturbances and flock size were illustrated using a generalized linear model.Results:In the early and middle wintering periods,the Hooded Crane used paddy fields as its major foraging habitat,where the number of foraging birds and flocks were the highest.During the late period,the cranes took to meadows as their major foraging habitat.The variation among foraging flock was mainly embodied in the size of the flocks,while the age composition of these flocks did not change perceptibly.Family flocks were notably different from flock groups in size and age composition.The results of a generalized linear model showed that the food abundance had a marked effect on foraging flock size and age composition,while disturbances had a significant effect only on flock size.From our analysis,it appeared that the combined effect of the two variables was significant on the size of the foraging flock,but had less impact on age composition.Conclusions:Food abundance and disturbances affected the flock size of the Hooded Crane.With abundant food and high disturbances,flock sizes increased owing to cooperation in foraging.To avoid competition and maximize foraging benefits,flock size reduces with an abundance of food but low disturbance.By trading off risks and costs,the cranes showed flexible flock distributions and a variety of foraging strategies to maximize benefits and to improve their fitness. 展开更多
关键词 FLOCK pattern Food abundance DISTURBANCE Hooded crane
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A practical fuzzy controllers scheme of overhead crane 被引量:9
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作者 Chengyuan CHANG Shihwei HSU Kuohung CHIANG 《控制理论与应用(英文版)》 EI 2005年第3期266-270,共5页
This paper presents fuzzy-based design for the control of overhead crane. Instead of analyzing the complex nonlinear crane system, the proposed approach uses simple but effective way to control the crane. There are tw... This paper presents fuzzy-based design for the control of overhead crane. Instead of analyzing the complex nonlinear crane system, the proposed approach uses simple but effective way to control the crane. There are twin fuzzy controllers which deal with the feedback information, the position of trolley crane and the swing angle of load, to suppress the sway and accelerate the speed when the crane transports the heavy load. This approach simplifies the designing procedure of crane controller; besides, the twin controller method reduces the rule number when fulfilling the fuzzy system. Finally, experimental results through the crane model demonstrate the effectiveness of the scheme. 展开更多
关键词 Overhead crane Fuzzy Control
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Variational analysis of mid-span deflection of gantry cranes 被引量:3
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作者 ZHANG Da-peng CHENG Wen-ming WANG Bin 《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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A global overview of cranes: status, threats and conservation priorities 被引量:11
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作者 James HARRIS Claire MIRANDE 《Chinese Birds》 CSCD 2013年第3期189-209,共21页
This paper reviews the population trends and threats for the 15 species of cranes, and comments on conservation priorities for the family as a whole. Cranes occur on ifve continents, with greatest diversity in East As... This paper reviews the population trends and threats for the 15 species of cranes, and comments on conservation priorities for the family as a whole. Cranes occur on ifve continents, with greatest diversity in East Asia (nine species) and Sub-Saharan Africa (six species). Eleven crane species are threatened with extinction according to the IUCN Red List, including one species Critically En-dangered, three species Endangered, and seven species Vulnerable. Of the four species of Least Con-cern, population sizes for the Demoiselle (Anthropoides virgo) and Brolga (Grus rubicunda) are not well known but these species are declining in some areas. The Sandhill (G. canadensis) and Eurasian Cranes (G. grus) are the most abundant cranes and have rapidly increased in part due to their lfexible selection of foraging habitats and use of agriculture lands and waste grain as a food source. Status for six species-Grey Crowned (Balearica regulorum), Blue (Anthropoides paradise), Black-necked (G. nigricollis), Red-crowned (G. japonensis), Sandhill, and Siberian (G. leucogeranus)-are summarized in more detail to illustrate the diversity of population shifts and threats within the crane family. A crane threat matrix lists the major threats, rates each threat for each species, and scores each threat for the crane family as a whole. Four of the ifve greatest threats are to the ecosystems that cranes depend upon, while only one of the top threats (human disturbance) relates to human action directly impact-ing on cranes. Four major threats are discussed:dams and water diversions, agriculture development, crane trade, and climate change. Conservation efforts should be strongly science-based, reduce direct threats to the birds, safeguard or restore habitat, and strengthen awareness among decision makers and local communities for how to safeguard cranes and wetlands. Especially for the most severely threatened species, signiifcantly stronger efforts will be needed to incorporate our understanding of the needs of cranes and the ecosystems they inhabit into decisions about agriculture, water manage-ment, energy development and other human activities. 展开更多
关键词 craneS climate change habitat loss WETLANDS wildlife trade
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Intelligent Optimization Methods for the Design of an Overhead Travelling Crane 被引量:5
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作者 QU Xiaogang XU Gening +1 位作者 FAN Xiaoning BI Xiaoheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第1期187-196,共10页
In design optimization of crane metal structures, present approaches are based on simple models and mixed variables, which are difficult to use in practice and usually lead to failure of optimized results for rounding... In design optimization of crane metal structures, present approaches are based on simple models and mixed variables, which are difficult to use in practice and usually lead to failure of optimized results for rounding variables. Crane metal structure optimal design(CMSOD) belongs to a constrained nonlinear optimization problem with discrete variables. A novel algorithm combining ant colony algorithm with a mutation-based local search(ACAM) is developed and used for a real CMSOD for the first time. In the algorithm model, the encoded mode of continuous array elements is introduced. This not only avoids the need to round optimization design variables during mixed variable optimization, but also facilitates the construction of heuristic information, and the storage and update of the ant colony pheromone. Together with the proposed ACAM, a genetic algorithm(GA) and particle swarm optimization(PSO) are used to optimize the metal structure of a crane. The optimization results show that the convergence speed of ACAM is approximately 20% of that of the GA and around 11% of that of the PSO. The objective function value given by ACAM is 22.23% less than the practical design value, a reduction of 16.42% over the GA and 3.27% over the PSO. The developed ACAM is an effective intelligent method for CMSOD and superior to other methods. 展开更多
关键词 crane metal structure design optimization continuous array element encoded model ant colony optimization particle swarm optimization genetic algorithm
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Population sizes and group characteristics of Siberian Crane(Leucogeranus leucogeranus) and Hooded Crane(Grus monacha) in Poyang Lake Wetland 被引量:3
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作者 Ming-Qin SHAO Hong GUO +1 位作者 Jian-Hong JIANG 《Zoological Research》 CAS CSCD 北大核心 2014年第5期373-379,共7页
Both the Siberian Crane(Leucogeranus leucogeranus) and Hooded Crane(Grus monacha) have limited population sizes and are considered endangered by domestic Chinese and international agencies.To document the current size... Both the Siberian Crane(Leucogeranus leucogeranus) and Hooded Crane(Grus monacha) have limited population sizes and are considered endangered by domestic Chinese and international agencies.To document the current size of their respective populations and characterize their groups,between October 2012 and April 2013 we undertook fieldwork at four nature reserve areas within the Poyang Lake wetlands.We divided Poyanghu National Nature Reserve(PYH) into the Wucheng(PWC) and Hengfeng areas(PHF),because each are each located in different counties.Our fieldwork showed that the Siberian Crane occurred mainly in PYH(364 in the PHF,158 in the PWC) and the Nanjishan Wetland National Nature Reserve(NJS,with 200 individuals).The Hooded Crane was mainly distributed in PYH(302 in the PHF and 154 in the PWC).Family groups accounted for more than 50% of the total number of groups among both species,with Hooded Cranes forming more family groups than Siberian Cranes.Typically,these groups were formed of two adults with one offspring(Siberian Crane),and two adults with two offspring(Hooded Crane),with the mean family group size of the Siberian Crane and Hooded Crane being respectively 2.65±0.53(n=43) and 3.09±0.86(n=47) individuals per group.The mean collective group size of the Siberian Crane and Hooded Crane included 28.09±24.94(n=23) and 28.94±27.97(n=16) individuals per group,respectively,with the proportion of juveniles among Hooded Cranes being more than double that seen among the Siberian Cranes. 展开更多
关键词 Siberian crane Hooded crane Group characteristics Poyang Lake wetland
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