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The intrinsic developmental age signal defines an age-dependent climbing behavior in cucumber
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作者 Zezhou Hong Xinrui Wang +7 位作者 Zipei Fan Jiahao Wang Aiyi Yang Guochao Yan Yong He Huasen Wang Zhujun Zhu Yunmin Xu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期797-808,共12页
The tendril is a climbing organ in cucurbits and functions in physical support and to avoid shading by neighboring vegetation.However,how cucurbits produce tendrils to obtain climbing ability is largely unknown.In thi... The tendril is a climbing organ in cucurbits and functions in physical support and to avoid shading by neighboring vegetation.However,how cucurbits produce tendrils to obtain climbing ability is largely unknown.In this study,tendril phenotypes were investigated during different developmental stages.Our results revealed that tendril growth exhibited an age-dependent pattern in cucurbits.Tendril growth was inhibited,and the tendril was formed as a short tendril[nonfunctional tendril(nonF-tendril),approximately 0.1 cm]during the seedling stage.In contrast,enhanced cell proliferation and cell expansion led to rapid elongation of the tendril during the climbing stage,and the tendril formed as a functional tendril(F-tendril,approximately 30 cm)to obtain climbing ability.RT-qPCR detection showed that age-dependent tendril growth correlated negatively with the abundance of the conserved age regulator CsmiR156.Defoliation induced CsmiR156 to inhibit CsSPLs,and F-tendril formation and climbing ability were delayed in defoliated cucumbers,which confirmed the role of CsmiR156 in regulating tendril growth in vivo.Additionally,exogenous gibberellin(GA)treatment showed that GA positively regulated tendril growth,and RT-qPCR detection showed that the GA bio-synthetic genes and metabolic genes were affected by age pathway,suggesting that the age pathway depended on GA bio-synthetic and metabolic pathway to regulate cell expansion to determine tendril growth.In summary,our work reveals that change in tendril type is an important marker of phase transition in cucumber,and tendril growth is regulated by an intrinsic developmental age signal,ensuring that the cucumber obtains climbing ability at a suitable age. 展开更多
关键词 CUCUMBER TENDRIL Age CsmiR156 CsSPL Climbing ability
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Uphill or downhill?Cropland use change and its drivers from the perspective of slope spectrum
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作者 PAN Sipei LIANG Jiale +1 位作者 CHEN Wanxu PENG Yelin 《Journal of Mountain Science》 SCIE CSCD 2024年第2期484-499,共16页
The continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food security.Slope spectrum analysis of topographic and geomorphi... The continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food security.Slope spectrum analysis of topographic and geomorphic features is considered as a digital terrain analysis method which reflects the macro-topographic features by using micro-topographic factors.However,pieces of studies have extended the concept of slope spectrum in the field of geoscience to construction land to explore its expansion law,while research on the slope trend of cropland from that perspective remains rare.To address the gap,in virtue of spatial analysis and geographically weighted regression(GWR)model,the cropland use change in the Yangtze River Basin(YRB)from 2000 to 2020 was analyzed and the driving factors were explored from the perspective of slope spectrum.Results showed that the slope spectrum curves of cropland area-frequency in the YRB showed a first upward then a downward trend.The change curve of the slope spectrum of cropland in each province(municipality)exhibited various distribution patterns.Quantitative analysis of morphological parameters of cropland slope spectrum revealed that the further down the YRB,the stronger the flattening characteristics,the more obvious the concentration.The province experienced the greatest downhill cropland climbing(CLC)was Shannxi,while province experienced the highest uphill CLC was Zhejiang.The most common cropland use change type in the YRB was horizontal expansion type.The factors affecting average cropland climbing index(ACCI)were quite stable in different periods,while population density(POP)changed from negative to positive during the study period.This research is of practical significance for the rational utilization of cropland at the watershed scale. 展开更多
关键词 Cropland climbing Land use change Slope spectrum Driving factors Geographically weighted regression Yangtze River Basin
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词汇类型学视域下“爬”“挠”“刨”“挖”等动词的语义演变及共时语义关联
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作者 任鹏波 《湖南大学学报(社会科学版)》 北大核心 2024年第1期88-95,共8页
“爬”“挠”“刨”“挖”等汉语动词的历时语义演变路径,以及现代汉语方言中有关的同词化多义现象,表现出{挖掘}(DIG)、{搔挠}(SCRATCH)、{攀爬}(CLIMB)三个概念之间较强的关联性。汉语历时语料呈现的语义演变方向为SCRATCH→DIG或SCRA... “爬”“挠”“刨”“挖”等汉语动词的历时语义演变路径,以及现代汉语方言中有关的同词化多义现象,表现出{挖掘}(DIG)、{搔挠}(SCRATCH)、{攀爬}(CLIMB)三个概念之间较强的关联性。汉语历时语料呈现的语义演变方向为SCRATCH→DIG或SCRATCH→CLIMB,具有单向性。这种语义关联模式符合一定的语言共性,可以得到词汇类型学跨语言考察的支持,同时,可以根据汉语实际为词汇类型学增补SCRATCH→CLIMB型语义关联。 展开更多
关键词 {挖掘}(DIG) {搔挠}(SCRATCH) {攀爬}(CLIMB) 语义演变 语义关联
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"I Climbed the Great Wall"
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作者 MAN SUJIE 《Women of China》 1996年第7期4-4,共1页
I finally climbed the Great Wall, A dream of my childhood; my heart is filled with pleasure at the indescribable beauty of the Wall. China’s ancient civilization is best documented by the grandeur of the Wall.
关键词 I climbed the Great Wall
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Stair climbing,genetic predisposition,and the risk of incident type 2 diabetes:A large population-based prospective cohort study
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作者 Yuanjue Wu Mengyun Luo +1 位作者 Xiao Tan Liangkai Chen 《Journal of Sport and Health Science》 SCIE CSCD 2023年第2期158-166,共9页
Background:Cross-sectional evidence and small-scale trials suggest positive effects of stair climbing on cardiometabolic disease and glucose regulation.However,few studies have examined the long-term association betwe... Background:Cross-sectional evidence and small-scale trials suggest positive effects of stair climbing on cardiometabolic disease and glucose regulation.However,few studies have examined the long-term association between stair climbing and the incidence of type 2 diabetes(T2D).We aimed to prospectively evaluate the association of stair climbing with T2D and assess modifications by genetic predisposition to T2D.Methods:We included 451,699 adults(mean age=56.3±8.1 years,mean±SD;55.2%females)without T2D at baseline in the UK Biobank and followed up to March 31,2021.Stair climbing information was collected through the touchscreen questionnaire.Genetic risk score for T2D consisted of 424 single nucleotide polymorphisms.Results:During a median follow up of 12.1 years,14,896 T2D cases were documented.Compared with participants who reported no stair climbing,those who climbed stairs regularly had a lower risk of incident T2D(10-50 steps/day:hazard ratio(HR)=0.95,95%confidence interval(95%CI):0.89-1.00;60-100 steps/day:HR=0.92,95%CI:0.87-0.98;110-150 steps/day:HR=0.86,95%CI:0.80-0.91;>150 steps/day:HR=0.93,95%CI:0.87-0.99,p for trend=0.0007).We observed a significant interaction between stair climbing and genetic risk score on the subsequent T2D risk(p for interaction=0.0004),where the risk of T2D showed a downward trend in subjects with low genetic risk and those who reported stair climbing activity of 110-150 steps/day appeared to have the lowest overall T2D risk among those with intermediate to high genetic risk.Conclusion:A higher number of stairs climbed at home was associated with lower T2D incidence risk,especially among individuals with a low genetic predisposition to T2D.These findings highlight that stair climbing,as incidental physical activity,offers a simple and low-cost complement to public health interventions for T2D prevention. 展开更多
关键词 COHORT Genetic risk score Stair climbing Type 2 diabetes UK Biobank
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The enhancement of performance and imbibition effect of slickwater-based fracturing fluid by using MoS_(2)nanosheets
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作者 Hang Xu Yuan Li +6 位作者 Guo-Lin Yu Sa-Sa Yang Bo-Jun Li Fu-Jian Zhou Er-Dong Yao Hao Bai Zhi-Yu Liu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2187-2201,共15页
Slickwater-based fracturing fluid has recently garnered significant attention as the major fluid for volumetric fracturing;however,lots of challenges and limitations such as low viscosity,poor salt tolerance,and possi... Slickwater-based fracturing fluid has recently garnered significant attention as the major fluid for volumetric fracturing;however,lots of challenges and limitations such as low viscosity,poor salt tolerance,and possible formation damage hinder the application of the conventional simple slickwater-based fracturing fluid.In addition,nanomaterials have proven to be potential solutions or improvements to a number of challenges associated with the slickwater.In this paper,molybdenum disulfide(MoS_(2))nanosheets were chemically synthesized by hydrothermal method and applied to improve the performance of conventional slickwater-based fracturing fluid.Firstly,the microstructure characteristics and crystal type of the MoS_(2)nanosheets were analyzed by SEM,EDS,TEM,XPS,and Raman spectroscopy techniques.Then,a series of evaluation experiments were carried out to compare the performance of MoS_(2)nanosheet-modified slickwater with the conventional slickwater,including rheology,drag reduction,and sand suspension.Finally,the enhanced imbibition capacity and potential mechanism of the nanosheet-modified slickwater were systematically investigated.The results showed that the self-synthesized MoS_(2)nanosheets displayed a distinct ultrathin flake-like morphology and a lateral size in the range of tens of nanometers.In the nano-composites,each MoS_(2)nanosheet plays the role of cross-linking point,so as to make the spatial structure of the entire system more compact.Moreover,nanosheet-modified slickwater demonstrates more excellent properties in rheology,drag reduction,and sand suspension.The nanosheet-modified slickwater has a higher apparent viscosity after shearing 120 min under 90℃ and 170 s^(−1).The maximum drag reduction rate achieved 76.3%at 20℃,and the sand settling time of proppants with different mesh in the nano-composites was prolonged.Spontaneous imbibition experiments showed that the gel-breaking fluid of nanosheet-modified slickwater exhibited excellent capability of oil-detaching,and increase the oil recovery to∼35.43%.By observing and analyzing the interfacial behavior of MoS_(2)nanosheets under stimulated reservoir conditions,it was found that the presence of an interfacial tension gradient and the formation of a climbing film may play an essential role in the spontaneous imbibition mechanism.This work innovatively uses two-dimensional MoS_(2)nanosheets to modify regular slickwater and confirms the feasibility of flake-like nanomaterials to improve the performance of slickwater.The study also reveals the underlying mechanism of enhanced imbibition efficiency of the nano-composites. 展开更多
关键词 Slickwater-based fracturing fluid MoS_(2)nanosheet Performance evaluation spontaneous imbibition Climbing film
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Efficient Clustering Using Memetic Adaptive Hill Climbing Algorithm in WSN
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作者 M.Manikandan S.Sakthivel V.Vivekanandhan 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3169-3185,共17页
Wireless Sensor Networks are composed of autonomous sensing devices which are interconnected to form a closed network.This closed network is intended to share sensitive location-centric information from a source node ... Wireless Sensor Networks are composed of autonomous sensing devices which are interconnected to form a closed network.This closed network is intended to share sensitive location-centric information from a source node to the base station through efficient routing mechanisms.The efficiency of the sensor node is energy bounded,acts as a concentrated area for most researchers to offer a solution for the early draining power of sensors.Network management plays a significant role in wireless sensor networks,which was obsessed with the factors like the reliability of the network,resource management,energy-efficient routing,and scalability of services.The topology of the wireless sensor networks acts dri-ven factor for network efficiency which can be effectively maintained by perform-ing the clustering process effectively.More solutions and clustering algorithms have been offered by various researchers,but the concern of reduced efficiency in the routing process and network management still exists.This research paper offers a hybrid algorithm composed of a memetic algorithm which is an enhanced version of a genetic algorithm integrated with the adaptive hill-climbing algorithm for performing energy-efficient clustering process in the wireless sensor networks.The memetic algorithm employs a local searching methodology to mitigate the premature convergence,while the adaptive hill-climbing algorithm is a local search algorithm that persistently migrates towards the increased elevation to determine the peak of the mountain(i.e.,)best cluster head in the wireless sensor networks.The proposed hybrid algorithm is compared with the state of art clus-tering algorithm to prove that the proposed algorithm outperforms in terms of a network life-time,energy consumption,throughput,etc. 展开更多
关键词 Wireless sensor networks TOPOLOGY CLUSTERING memetic algorithm adaptive hill climbing algorithm network management energy consumption THROUGHPUT
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Investigation on the Effect of the Tension Degree of Tracks on the Adsorption Performance of Tracked Wall Climbing Robot
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作者 Shun Xiao Guangping He +3 位作者 Jiejian Di Jie Zhang Zhonghai Zhang Lin Zhou 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第1期52-60,共9页
In this paper,a new tracked wall climbing robot with permanent magnetic units is designed,and the tension degree of robot’s tracks is found to have a significant impact on the robot’s adsorption performance.This tra... In this paper,a new tracked wall climbing robot with permanent magnetic units is designed,and the tension degree of robot’s tracks is found to have a significant impact on the robot’s adsorption performance.This tracked wall climbing robot is a remotely controlled robot.All the control devices can be installed on the robot body.All the permanent magnetic units are arranged on the light track.In order to illustrate the relationship between the tension degree and the adsorption performance,when absorbed on the vertical surface and 180⁃degree inverted surface,the static force analysis of the robot is presented.Finally,experiments were demonstrated to prove that higher tension degree of tracks can make adsorption performance better. 展开更多
关键词 permanent magnetic adsorption TRACK tension degree wall climbing robot
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Prediction of Link Failure in MANET-IoT Using Fuzzy Linear Regression
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作者 R.Mahalakshmi V.Prasanna Srinivasan +1 位作者 S.Aghalya D.Muthukumaran 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1627-1637,共11页
A Mobile Ad-hoc NETwork(MANET)contains numerous mobile nodes,and it forms a structure-less network associated with wireless links.But,the node movement is the key feature of MANETs;hence,the quick action of the nodes ... A Mobile Ad-hoc NETwork(MANET)contains numerous mobile nodes,and it forms a structure-less network associated with wireless links.But,the node movement is the key feature of MANETs;hence,the quick action of the nodes guides a link failure.This link failure creates more data packet drops that can cause a long time delay.As a result,measuring accurate link failure time is the key factor in the MANET.This paper presents a Fuzzy Linear Regression Method to measure Link Failure(FLRLF)and provide an optimal route in the MANET-Internet of Things(IoT).This work aims to predict link failure and improve routing efficiency in MANET.The Fuzzy Linear Regression Method(FLRM)measures the long lifespan link based on the link failure.The mobile node group is built by the Received Signal Strength(RSS).The Hill Climbing(HC)method selects the Group Leader(GL)based on node mobility,node degree and node energy.Additionally,it uses a Data Gathering node forward the infor-mation from GL to the sink node through multiple GL.The GL is identified by linking lifespan and energy using the Particle Swarm Optimization(PSO)algo-rithm.The simulation results demonstrate that the FLRLF approach increases the GL lifespan and minimizes the link failure time in the MANET. 展开更多
关键词 Mobile ad-hoc network fuzzy linear regression method link failure detection particle swarm optimization hill climbing
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两种提高双射S盒非线性度的方法及其比较 被引量:2
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作者 于亦舟 欧海文 《中国新通信》 2007年第3期36-39,共4页
S盒是分组密码中重要的非线性部件,S盒的密码性质直接影响了密码算法的安全性,一个好的S盒要求有较高的非线性度。本文介绍了两种改善双射S盒非线性度的方法:Hill Climbing算法和它的改进算法,并对这两种方法进行比较。
关键词 S盒 非线性度 HILL Climbing算法
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Gabor变换在仿真模型验证中的应用 被引量:4
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作者 白瑞阳 吴晓燕 +1 位作者 张玉新 姚春明 《弹箭与制导学报》 CSCD 北大核心 2014年第4期187-188,195,共3页
仿真模型验证是从模型预期使用的角度出发,确定模型和有关数据代表真实世界正确程度的过程,是VV&A工作的重要内容之一。针对传统验证方法不能将仿真数据和试验数据的时频域特性结合起来综合分析的特点,从时频联合分析的思想出发,将G... 仿真模型验证是从模型预期使用的角度出发,确定模型和有关数据代表真实世界正确程度的过程,是VV&A工作的重要内容之一。针对传统验证方法不能将仿真数据和试验数据的时频域特性结合起来综合分析的特点,从时频联合分析的思想出发,将Gabor变换引入仿真模型验证中,实现了对仿真数据和试验数据时频域的综合分析。实例分析表明,该方法可以提高模型验证的准确性,具有一定的实用性。 展开更多
关键词 GABOR变换 模型验证 CLIMB方案
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黔产千里光提取物总生物碱的含量测定及抗菌作用研究 被引量:5
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作者 饶海 周镁 +2 位作者 秦拴梅 黄秀平 覃容贵 《安徽农业科学》 CAS 2013年第14期6207-6209,共3页
[目的]比较黔产千里光不同溶剂提取物总生物碱的含量及其抗菌作用。[方法]采用紫外可见分光光度法测定千里光中总生物碱的含量,并采用牛津杯法观察各提取物的抗菌作用。[结果]采用紫外可见分光光度法测定千里光中总生物碱浓度在0.011 0... [目的]比较黔产千里光不同溶剂提取物总生物碱的含量及其抗菌作用。[方法]采用紫外可见分光光度法测定千里光中总生物碱的含量,并采用牛津杯法观察各提取物的抗菌作用。[结果]采用紫外可见分光光度法测定千里光中总生物碱浓度在0.011 0~0.055 0 mg/ml范围内与吸光度的线性关系良好,回归方程为Y=23.654X+0.021,平均回收率为99.2%,R=0.999 9。千里光浓度60%醇提液总生物碱含量为38.71 mg/g,浓度95%醇提液生物碱含量为52.25 mg/g,水煎液总生物碱含量为60.50 mg/g。浓度60%乙醇提取液对肺炎链球菌、金黄色葡萄球菌和大肠杆菌抑制作用较强;水提液对大肠杆菌抑制作用较强;浓度95%乙醇提取液抗菌作用较弱,对绿脓杆菌无抑制作用。[结论]该方法准确、简便、重复性好,可用于黔产千里光中生物碱的含量测定;千里光提取物总生物碱的含量与其抗菌作用无正相关关系。 展开更多
关键词 千里光(Climbing Groundsel Herb) 总生物碱 紫外可见分光光度法 抗菌作用
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扫除母语影响,丰富小学英语教学策略
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作者 何洁 《学子(理论版)》 2015年第1期35-35,共1页
任何语言的学习都需要良好的语言环境,汉语是我国的第一大母语,学生长期处于悠久的汉字文化当中,当学习新语言时,会感到一定的难度甚至产生一些抵触情绪。特别是小学生,刚接触一门新语言,既会对外语产生好奇心,也会有或多或少的对新语... 任何语言的学习都需要良好的语言环境,汉语是我国的第一大母语,学生长期处于悠久的汉字文化当中,当学习新语言时,会感到一定的难度甚至产生一些抵触情绪。特别是小学生,刚接触一门新语言,既会对外语产生好奇心,也会有或多或少的对新语言的学习而产生的害怕心理。小学英语教师应考虑到这一可能出现的情况,丰富自己的教学策略以扫除母语的影响,让学生轻松学好英语。从长期的教学实践看,要扫除母语的负面影响。 展开更多
关键词 英语教学策略 小学英语教师 汉字文化 害怕心理 英文歌曲 新单词 转换形式 记忆困难 CLIMBING today
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A Biomimetic Climbing Robot Based on the Gecko 被引量:18
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作者 Carlo Menon Metin Sitti 《Journal of Bionic Engineering》 SCIE EI CSCD 2006年第3期115-125,共11页
The excellent climbing performance of the gecko is inspiring engineers and researchers for the design of artificial systems aimed at moving on vertical surfaces. Climbing robots could perform many useful tasks such as... The excellent climbing performance of the gecko is inspiring engineers and researchers for the design of artificial systems aimed at moving on vertical surfaces. Climbing robots could perform many useful tasks such as surveillance, inspection, repair, cleaning, and exploration. This paper presents and discusses the design, fabrication, and evaluation of two climbing robots which mimic the gait of the gecko. The first robot is designed considering macro-scale operations on Earth and in space. The second robot, whose motion is controlled using shape memory alloy actuators, is designed to be easily scaled down for micro-scale applications. Proposed bionic systems can climb up 65 degree slopes at a speed of 20 mm·s^-1. 展开更多
关键词 GECKO ROBOTICS biomimetics CLIMBING space memory alloy
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Multi-Scale Compliant Foot Designs and Fabrication for Use with a Spider-Inspired Climbing Robot 被引量:10
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作者 Dan Sameoto Carlo Menon 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第3期189-196,共8页
Climbing robots are of potential use for surveillance, inspection and exploration in different environments. In particular, the use of climbing robots for space exploration can allow scientists to explore environments... Climbing robots are of potential use for surveillance, inspection and exploration in different environments. In particular, the use of climbing robots for space exploration can allow scientists to explore environments too challenging for traditional wheeled designs. To adhere to surfaces, biomimetic dry adhesives based on gecko feet have been proposed. These biomimetic dry adhesives work by using multi-scale compliant mechanisms to make intimate contact with different surfaces and adhere by using Van der Waals forces. Fabrication of these adhesives has frequently been challenging however, due to the difficulty in combining macro, micro and nanoscale compliance. We present an all polymer foot design for use with a hexapod climbing robot and a fabrication method to improve reliability and yield. A high strength, low-modulus silicone, TC-5005, is used to form the foot base and microscale fibres in one piece by using a two part mold. A macroscale foot design is produced using a 3D printer to produce a base mold, while lithographic definition of microscale fibres in a thick photoresist forms the 'hairs' of the polymer foot. The adhesion of the silicone fibres by themselves or attached to the macro foot is examined to determine best strategies for placement and removal of feet to maximize adhesion. Results demonstrate the successful integration of micro and macro compliant feet for use in climbing on a variety of surfaces. 展开更多
关键词 biomimetics dry adhesive GECKO climbing robot MEMS SILICONE
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MICROSTRUCTURAL EVOLUTION AND MECHANISMS OF SUPERPLASTICITY IN LARGE GRAINED IRON ALUMINIDES 被引量:7
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作者 Dongliang Lin (T.L.Lin) and Yi Liu Open Laboratory of Education Ministry of China for High Temperature Materials Tests, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030, China 《中国有色金属学会会刊:英文版》 CSCD 1999年第S1期228-239,共12页
The superplastic behavior has been found in Fe 3Al and FeAl alloys with grain sizes of 100~600 μm. The large grained Fe 3Al and FeAl alloys exhibit all deformation characteristics of conventional fine grain size sup... The superplastic behavior has been found in Fe 3Al and FeAl alloys with grain sizes of 100~600 μm. The large grained Fe 3Al and FeAl alloys exhibit all deformation characteristics of conventional fine grain size superplastic alloys. However, superplastic behavior was found in large grained iron aluminides without the usual prerequisites for the superplasticity of a fine grain size and grain boundary sliding. The metallographic examinations have shown that average grain size of large grained iron aluminides decreased during superplastic deformation. Transmission electron microscopy (TEM) observations have shown that there were a great number of subgrain boundaries which formed a network and among which the proportion of low and high angle boundaries increased with the increase of strain. The observed superplastic phenomenon is explained by continuous recovery and recrystallization. During superplastic deformation, an unstable subgrain network forms and these subboundaries absorb gliding dislocations and transform into low and high angle grain boundaries. A dislocation gliding and climb process accommodated by subboundary sliding, migration and rotation, allows the superplastic flow to proceed. 展开更多
关键词 iron ALUMINIDES SUPERPLASTICITY mechanism microstructural evolution DISLOCATION GLIDING DISLOCATION CLIMB SUPERPLASTIC flow
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Berberine Prolongs Life Span and Stimulates Locomotor Activity of <i>Drosophila melanogaster</i> 被引量:5
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作者 V. V. Navrotskaya G. Oxenkrug +1 位作者 L. I. Vorobyova P. Summergrad 《American Journal of Plant Sciences》 2012年第7期1037-1040,共4页
Drosophila melanogaster mutants with deficient kynurenine (KYN) formation from tryptophan (TRP) have longer life span than wild type flies. Administration of alpha-methyl-TRP and 5-methyl-TRY, the inhibitors of TRP-KY... Drosophila melanogaster mutants with deficient kynurenine (KYN) formation from tryptophan (TRP) have longer life span than wild type flies. Administration of alpha-methyl-TRP and 5-methyl-TRY, the inhibitors of TRP-KYN metabolism, prolonged life span in wild-type flies. Both inhibitors are not available for human use. Berberine, an isoquinoline alkaloid isolated from berberis aristata is known as the herb widely used in traditional Chinese and Indian medicine. Berberin is a strong inhibitor of the enzyme catalyzing TRP conversion into KYN. Considering this particular feature we investigated the effect of berberine on life-and health-span in wild-type Drosophila melanogaster. The results of our study showed that Berberine extended mean, median and maximum life span of female flies. Berberine did not affect the number of pupae of filial generation and decreased their lethality. Berberine increased locomotor activity (vertical climbing). The results of the study suggest that berberine prolongs life- and improves health-span of Drosophila melanogaster. Berberine might be a candidate drug for prevention and treatment of aging and aging-associated medical and psychiatric disorders. 展开更多
关键词 BERBERINE Life Span Drosophila MELANOGASTER KYNURENINE Vertical CLIMBING Viability
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Complex experimental analysis of rifle-shooter interaction 被引量:2
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作者 Michal Taraszewski Janusz Ewertowski 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2017年第5期346-352,共7页
In this study, a complex analysis of a man-weapon interaction based on experimental effort is presented.The attention is focused on how a shooter can influence on a rifle, opposite to generally considered in literatur... In this study, a complex analysis of a man-weapon interaction based on experimental effort is presented.The attention is focused on how a shooter can influence on a rifle, opposite to generally considered in literature rifle's impact on a shooter. It is shown, based on the kbk AKM weapon, that each support point of the rifle has an substantial impact on the system. It is said that identifying human reactions on weapon may let to describe gun movement and thus may be applied to weapon accuracy determination. 展开更多
关键词 Rifle-shooter INTERACTION Man-weapon forces MUZZLE CLIMB FIREARM Recoil Accuracy
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Critical Suction Characteristic Analyses of a Wall Climbing Robot 被引量:2
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作者 徐代君 高学山 +3 位作者 吴晓兵 范宁军 李科杰 朱炜 《Journal of Beijing Institute of Technology》 EI CAS 2007年第2期135-139,共5页
A new method called critical suction is used based on the wall climbing robot demands of miniature structure, moving smartly and low noise. It makes the robot achieve the homeostasis state in the suction cup, and in t... A new method called critical suction is used based on the wall climbing robot demands of miniature structure, moving smartly and low noise. It makes the robot achieve the homeostasis state in the suction cup, and in this condition the robot can stay on the wall reliably and move smartly. The fluid mechanics model and fluid network model are set up to analyze the robot suction system when the airflow is steady or changes suddenly. Furthermore, simulation results indicate the close relation between the key parameters of robot structure and the suction system. Finally the method of critical suction proves correct in theory. 展开更多
关键词 wall climbing robot critical suction fluid mechanics fluid network
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Trial mountain climbing algorithm for solving the inverse kinematics of redundant manipulator 被引量:3
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作者 周友行 何清华 邓伯禄 《Journal of Central South University of Technology》 2002年第4期285-288,共4页
Trial mountain climbing algorithm to solve the inverse kinematics problem of redundant manipulator is introduced, and a method of describing a numeral with a special numeration system is given to define the changed st... Trial mountain climbing algorithm to solve the inverse kinematics problem of redundant manipulator is introduced, and a method of describing a numeral with a special numeration system is given to define the changed step of the trail mountain climbing algorithm. The results show that a likelihood solution can be found quickly in the infinite groups of likelihood solutions within the limited search times, and need not calculate the anti trigonometric function and the inverse matrix. In addition, this algorithm has many good qualities such as concise algorithm, tiny computation, fast convergence velocity, good stability and extensive adaptability. 展开更多
关键词 MANIPULATOR tunnel-drilling robot KINEMATICS equation TRIAL MOUNTAIN CLIMBING ALGORITHM
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