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Fossil-Winged Fruits of Fraxinus(Oleaceae) and Liriodendron(Magnoliaceae) from the Duho Formation,Pohang Basin,Korea 被引量:3
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作者 Seung-Ho JUNG Seong-Joo LEE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第5期845-852,共8页
A total of 16 specimens of fossil-winged fruits were found from the Middle Miocene marine deposits, Duho Formation, Pohang Basin, Korea. They were identified into two structurally different groups: 15 specimens into ... A total of 16 specimens of fossil-winged fruits were found from the Middle Miocene marine deposits, Duho Formation, Pohang Basin, Korea. They were identified into two structurally different groups: 15 specimens into a winged fruit of Fraxinus, and one specimen of Liriodendron. The most samaras (13 specimens) were identified as Fraxinus oishii, which is characterized by narrowly ovate or ovate-elliptic shapes that are 2.7-3.6 cm in length and 0.7-1 cm in width (i/w ratio=3.4-4). The apexes of the Fraxinus oishii samara are round or slightly emarginated, and a seed of the samara is always located at the base, of which the general shape is narrow rhombic-ellipsoidal. The seed is 1.2-2 cm long and 0.5-0.7 cm wide. Two specimens are different from the samara of Fraxinus oishii. They have a 6.6 length/width ratio (3.3 cm long and 0.5 cm wide), and thus, are temporarily classified into the Fraxinus sp. One specimen was recognized as a winged seed of Liriodendron meisenense. The wing is broadly lanceolate to elliptic in shape, has a smooth, acute apex, and is approximately 3 cm long and 0.7 cm wide. Samaras of Fraxinus oishii and Liriodendron meisenense were early reported from the Middle Miocene deposits from North Korea, but these specimens are the first discovery in South Korea. Further study of the Duho Formation may connect flora relationships between North and South Korea. 展开更多
关键词 winged fruits FRAXINUS LIRIODENDRON Middle Miocene Pohang Basin Korea
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Dispersal and germination of winged seeds of Brandisia hancei,a shrub in karst regions of China
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作者 Yongquan Ren Chengling Huang +2 位作者 Jiaming Zhang Yongpeng Ma Xiaoling Tian 《Plant Diversity》 SCIE CAS CSCD 2021年第3期234-238,共5页
Brandisia hancei(Paulowniaceae)is a widely distributed shrub in karst regions in southwestern China.Its seeds have a membranous wing,and they mature just before the rainy season begins.To assess the effect of the wing... Brandisia hancei(Paulowniaceae)is a widely distributed shrub in karst regions in southwestern China.Its seeds have a membranous wing,and they mature just before the rainy season begins.To assess the effect of the wing on seed dispersal and germination of B.hancei,we measured the dispersal distance at varying wind speeds and release heights,falling duration from different release heights,floating duration on still water,rates of imbibition of water,and drying and soil adherence to seeds.Germination experiments were conducted on intact and de-winged seeds immediately after harvest.The wing increased the falling duration in still air and the floating ability on water.Dispersal distance of winged and de-winged seeds did not differ at a wind speed of 2.8 m s1,but at 3.6 and 4.0 m s1 dispersal distances were greater for de-winged than for winged seeds.Seed wing had little effect of absorption and retention of water,but significantly increased soil adherence to the seeds.Mature seeds were non-dormant and germinated to over 90%with a mean germination time of about 10 days.By combining the environmental conditions in karst habitat with the seed traits of B.hancei,we conclude that dispersal and germination of winged seeds are adapted to the precipitation seasonality in heterogeneous habitats absence of soil. 展开更多
关键词 ANEMOCHORY HYDROCHORY Membranous wing Seed dispersal winged seed
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Molecular genetic diversity of winged bean gene pool in Thailand assessed by SSR markers
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作者 Kularb Laosatit Kitiya Amkul +1 位作者 Sompong Chankaew Prakit Somta 《Horticultural Plant Journal》 SCIE CSCD 2022年第1期81-88,共8页
Winged bean[Psophocarpus tetragonolobus(L.)DC.]is a vegetable legume crop.The center of origin,diversity and domestication of this crop are not known.In this study,we assessed the genetic diversity and population stru... Winged bean[Psophocarpus tetragonolobus(L.)DC.]is a vegetable legume crop.The center of origin,diversity and domestication of this crop are not known.In this study,we assessed the genetic diversity and population structure of 457 accessions of winged bean collected from six geographical regions(North,Northeast,East,West,and central,and South)in Thailand using 14 simple sequence repeat(SSR)markers.In total,the SSR markers detected only 55 alleles with an average of 3.9 alleles per locus.Observed heterozygosity was relatively high(0.15)and overall gene diversity was moderate(0.487).Gene diversity,allelic richness and observed heterozygosity in the six regions were comparable,while the estimated out-crossing rate was relatively high(16.4%).STRUCTURE analysis grouped the 457 winged bean accessions into three subpopulations.Neighbor-joining(NJ)analysis grouped all the accessions into two major clusters.Genetic groups identified by both STRUCTURE analysis and NJ analysis were unrelated to geographical origins.Principal coordinate analysis revealed no clear clustering of the winged bean accessions.Although genetic groups were not unrelated to geographical origins,most of the winged bean accessions with long pods(30 cm or higher in length)or having purple seed coats or purple young pods were grouped together.This suggested that the winged beans with long pods or with purple seed or purple young pods may have a single origin.Altogether,these results demonstrated that the genetic diversity of winged bean in Thailand was moderate with high genetic admixture.We argue that the high genetic admixture of the winged bean in Thailand is due to seed migration and relatively high outcrossing rate. 展开更多
关键词 winged bean Psophocarpus tetragonolobus Underutilized crop DIVERSITY Population structure SSR
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GOLD AND SILVER WINGED GODS FROM THE TUBO PERIOD 被引量:1
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作者 Huo Wei 《China's Tibet》 2018年第1期54-57,共4页
Ethnic people living on the Tibetan Plateau during the Tubo period have been well-known as not only strong and brave on horses,but they were also an ethnic group enriched with powerful creativity and rich imagination.... Ethnic people living on the Tibetan Plateau during the Tubo period have been well-known as not only strong and brave on horses,but they were also an ethnic group enriched with powerful creativity and rich imagination.From Tubo’s cultural art,we can observe a large amount of extremely fine artifacts.For instance,among 展开更多
关键词 GOLD AND SILVER winged GODS FROM THE TUBO PERIOD
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Discrete element simulations and experiments of soil-winged subsoiler interaction 被引量:3
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作者 Xuezhen Wang Peng Li +2 位作者 Jinpu He Wuquan Wei Yuxiang Huang 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2021年第1期50-62,I0001,共14页
Understanding soil disturbance behaviors under the impact of the winged subsoiler is critical for designing or optimizing the winged subsoiler(a primary subsoiling tool).In this study,a soil-winged subsoiler interacti... Understanding soil disturbance behaviors under the impact of the winged subsoiler is critical for designing or optimizing the winged subsoiler(a primary subsoiling tool).In this study,a soil-winged subsoiler interaction model was developed and the effects of winged subsoiler on soil disturbance behaviors were investigated using the discrete element method(DEM)simulations and lab soil-bin tests.The results showed that wings mainly affected the disturbance range and fragmentation degree of soil above them.The draught forces of share section(SS),arc section in the hardpan(ASHP),arc section in the top layer(ASTL)and line section(LS)were accounted for 69.53%,25.22%,4.73%and 0.52%of the total draught force of winged subsoiler;the lateral disturbance range from high to low of the soil at different depths followed the ranking:top layer(TL),hardpan disturbed by arc section(HDAS)and hardpan disturbed by share section(HDSS).Wings had the greatest influence on the draught force of ASHP.Adding wings to an arc-shaped subsoiler increased the disturbance areas of HDAS,TL and HDSS by 47.52%,7.74%and 4.59%,respectively,but meanwhile increased the total draught force by 36%.Compared with a non-winged subsoiler,winged subsoiler had higher soil looseness(15.83%),soil disturbance coefficient(58.59%),furrow width(448.65 mm)and soil disturbance area ratio(0.3835),but poorer soil surface flatness(19.79 mm)and lower soil loosening efficiency(39.35 mm²/N).This study provided critical information for optimizing winged subsoilers on aspects of improving soil loosening effectiveness and reducing draught force. 展开更多
关键词 HARDPAN winged subsoiler draught force soil disturbance discrete element method(DEM) EXPERIMENT
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Development and formation of wing cuticle based on transcriptomic analysis in Locusta migratoria during metamorphosis
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作者 Jing Zhang Zhaochen Wu +5 位作者 Shuo Li He Huang Suning Liu Weimin Liu Xiaoming Zhao Jianzhen Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1285-1299,共15页
Wings are an important flight organ of insects.Wing development is a complex process controlled by a series of genes.The flightless wing pad transforms into a mature wing with the function of migratory flight during t... Wings are an important flight organ of insects.Wing development is a complex process controlled by a series of genes.The flightless wing pad transforms into a mature wing with the function of migratory flight during the nymphto-adult metamorphosis.However,the mechanism of wing morphogenesis in locusts is still unclear.This study analyzed the microstructures of the locust wing pads at pre-eclosion and the wings after eclosion and performed the comparative transcriptome analysis.RNA-seq identified 25,334 unigenesand 3,430 differentially expressed genes(DEGs)(1,907 up-regulated and 1,523 down-regulated).The DEGs mainly included cuticle development(LmACPs),chitin metabolism(Lm Idgf4),lipid metabolism-related genes,cell adhesion(Integrin),zinc finger transcription factors(LmSalm,LmZF593 andLmZF521),and others.Functional analysis based on RNA interference and hematoxylin and eosin(H&E)staining showed that the three genes encoded zinc finger transcription factors are essential for forming wing cuticle and maintaining morphology in Locusta migratoria.Finally,the study found that the LmSalm regulates the expression of LmACPs in the wing pads at pre-eclosion,and LmZF593 and LmZF521 regulate the expression of LmIntegrin/LmIdgf4/LmHMT420 in the wings after eclosion.This study revealed that the molecular regulatory axis controls wing morphology in nymphal and adult stages of locusts,offering a theoretical basis for the study of wing development mechanisms in hemimetabolous insects. 展开更多
关键词 Locusta migratoria wing development METAMORPHOSIS RNA-SEQ
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Structural design and modal behaviors analysis of a new swept baffled inflatable wing 被引量:1
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作者 Nuo Ma Li Liu +1 位作者 Fanmin Meng Junhui Meng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期382-398,共17页
Inflatable wing has significant application value in the design of loitering munitions because of its advantages such as lightweight and foldability.However,due to the flexible characteristics,aeroelastic behaviors of... Inflatable wing has significant application value in the design of loitering munitions because of its advantages such as lightweight and foldability.However,due to the flexible characteristics,aeroelastic behaviors of inflatable wings such as flutter are nonnegligible in flight.By designing a certain angle between the inflatable beam and the wing span,the structural dynamic and even the aeroelastic performance of the inflatable wing can be effectively improved.Based on the analysis of the mechanical and geometric characteristics of the inflatable structure,a new inflatable wing with sweep arranged inflatable beams is proposed,and the main design variables and methods are analyzed.For purpose of investigating the aeroelastic performance of the swept baffled inflatable wing,the modal behaviors by considering the wet mode are studied.In consideration of the deficiencies of the traditional wet modal analysis method,by introducing the influence on the additional stiffness of flow field,an added massstiffness method is proposed in this paper,and the advantages are verified by ground vibration experiments.On this basis,the effects of baffles sweep angle,pressure,and boundary conditions on the modal parameters and aeroelastic performance of inflatable wing are analyzed.The results show that the aeroelastic performance of the inflatable wing can be designed by changing the baffles sweep angle,which is enlightened for the aeroelastic tailoring design on inflatable wings. 展开更多
关键词 Inflatable wing Structural design Wet mode Flutter analysis
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Quantitative analysis of the morphing wing mechanism of raptors:Morphing kinematics of Falco peregrinus wing
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作者 唐迪 车婧琦 +4 位作者 金伟杰 崔亚辉 范忠勇 杨茵 刘大伟 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期68-77,共10页
Raptors are getting more attention from researchers because of their excellent flight abilities.And the excellent wing morphing ability is critical for raptors to achieve high maneuvering flight,which can be a good bi... Raptors are getting more attention from researchers because of their excellent flight abilities.And the excellent wing morphing ability is critical for raptors to achieve high maneuvering flight,which can be a good bionic inspiration for unmanned aerial vehicles(UAV)design.However,morphing wing motions of Falco peregrinus with multi postures cannot be consulted since such a motion database was nonexistent.This study aimed to provide data reference for future research in wing morphing kinetics.We used the computed tomography(CT)approach to obtain nine critical postures of the Falco peregrinus wing skeleton,followed with motion analysis of each joint and bone.Based on the obtained motion database,a six-bar kinematic model was proposed to regenerate wing motions with a high fidelity. 展开更多
关键词 RAPTOR wing morphing skeletal mechanism CT scans six-bar model
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Damage assessment of aircraft wing subjected to blast wave with finite element method and artificial neural network tool
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作者 Meng-tao Zhang Yang Pei +1 位作者 Xin Yao Yu-xue Ge 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期203-219,共17页
Damage assessment of the wing under blast wave is essential to the vulnerability reduction design of aircraft. This paper introduces a critical relative distance prediction method of aircraft wing damage based on the ... Damage assessment of the wing under blast wave is essential to the vulnerability reduction design of aircraft. This paper introduces a critical relative distance prediction method of aircraft wing damage based on the back-propagation artificial neural network(BP-ANN), which is trained by finite element simulation results. Moreover, the finite element method(FEM) for wing blast damage simulation has been validated by ground explosion tests and further used for damage mode determination and damage characteristics analysis. The analysis results indicate that the wing is more likely to be damaged when the root is struck from vertical directions than others for a small charge. With the increase of TNT equivalent charge, the main damage mode of the wing gradually changes from the local skin tearing to overall structural deformation and the overpressure threshold of wing damage decreases rapidly. Compared to the FEM-based damage assessment, the BP-ANN-based method can predict the wing damage under a random blast wave with an average relative error of 4.78%. The proposed method and conclusions can be used as a reference for damage assessment under blast wave and low-vulnerability design of aircraft structures. 展开更多
关键词 VULNERABILITY Wing structural damage Blast wave Battle damage assessment Back-propagation artificial neural network
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In-flight deformation measurement for high-aspect-ratio wing based on 3D speckle correlation
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作者 张兴国 HU Binghua +3 位作者 WANG Yuanliang YAN Hui MA Xiaodong GE Quanbo 《High Technology Letters》 EI CAS 2023年第3期257-268,共12页
In order to get an effective solution of the in-flight wing deformation measurement for high-wing aircrafts with high-aspect-ratio,a method based on three-dimensional(3D)speckle correlation technique is proposed.First... In order to get an effective solution of the in-flight wing deformation measurement for high-wing aircrafts with high-aspect-ratio,a method based on three-dimensional(3D)speckle correlation technique is proposed.Firstly,an in-flight wing deformation measurement system with two sets of conjugate cameras is designed based on structural characteristics and test requirements of high-wing aircrafts with large-aspect-ratio.Secondly,the in-flight wing deformation measurement method based on 3D speckle correlation technique is introduced including three aspects:measuring system and wing datum calibration,speckle image matching and 3D reconstruction,and wing deformation analysis.Fi-nally,ground simulation test of dynamic deformation measurement of a scaled model wing and flight test of dynamic deformation measurement of a large transport wing are carried out.The test results show that the measuring accuracy of single point coordinate in ground simulation test is better than 0.1 mm/m,in the airborne vibration environment,the static single-point positioning accuracy is bet-ter than 5 mm,and the in-flight wing deformation measurement data is well received by the flight test engineers.This method can satisfy the requirements of stability,reliability,high precision,non-con-tact and full-field measurement for dynamic deformation measurement of aircraft wing with high-as-pect-ratio. 展开更多
关键词 HIGH-ASPECT-RATIO three-dimensional(3D)speckle wing datum
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西黄胶囊联合TP方案对晚期非小细胞肺癌患者血清Foxp3、Ang-2水平的影响 被引量:2
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作者 刘小红 杨庆辉 +2 位作者 张永恒 王荦楠 袁红昌 《世界中西医结合杂志》 2022年第6期1214-1217,1222,共5页
目的探讨西黄胶囊联合TP方案治疗晚期非小细胞肺癌患者的临床疗效。方法选取2017年6月—2019年6月期间新乡医学院第一附属医院收治的晚期非小细胞肺癌患者86例,采用随机摸球法分为对照组和治疗组,每组各43例。对照组采用TP方案化疗,治... 目的探讨西黄胶囊联合TP方案治疗晚期非小细胞肺癌患者的临床疗效。方法选取2017年6月—2019年6月期间新乡医学院第一附属医院收治的晚期非小细胞肺癌患者86例,采用随机摸球法分为对照组和治疗组,每组各43例。对照组采用TP方案化疗,治疗组在此基础上加用西黄胶囊治疗。两组患者均连续治疗42 d后,观察两组患者近期疗效及不良反应发生情况,同时观察两组患者治疗前后中医证候症状积分、血清叉头翼状螺旋转录因子3(Forkhead or winged helix transcription,Foxp3)、血管生成素-2(Angiopoietin-2,Ang-2)、美国东部肿瘤协作组体能状况(Eastern cooperative oncology group performance status,ECOGPS)评分变化。结果治疗后治疗组有效率为46.51%、疾病控制率为83.72%,与对照组有效率25.38%、疾病控制率65.12%比较,差异有统计学意义(P<0.05)。治疗后,两组患者咳嗽、气短、胸闷、出汗、乏力、畏寒肢冷、腰膝酸软积分及总分较治疗前均降低,差异有统计学意义(P<0.05);且治疗组低于对照组,差异有统计学意义(P<0.05)。治疗后两组患者血清Foxp3、Ang-2水平较治疗前明显降低,差异有统计学意义(P<0.05);且治疗组低于对照组,差异有统计学意义(P<0.05)。治疗后两组ECOGPS评分均较治疗前降低,差异有统计学意义(P<0.05);且治疗组低于对照组(P<0.05)。治疗组发热(30.23%)、恶心呕吐(30.23%)、血小板减少(34.88%)、白细胞减少(41.86%)及肝肾功能损伤(30.23%)发生率与对照组(53.49%、60.47%、55.81%、48.84%、44.19%)比较,差异有统计学意义(P<0.05)。结论西黄胶囊联合TP方案治疗NSCLC的效果显著,能明显改善患者临床症状及体能状况,减轻化疗毒副反应,并降低血清Foxp3、Ang-2表达水平发挥抗癌作用。 展开更多
关键词 西黄胶囊 TP方案 晚期非小细胞肺癌 叉头翼状螺旋转录因子3(forkhead or winged helix transcription Foxp3) 血管生成素-2(angiopoietin-2 Ang-2)
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Decomposition of Mathematical Programming Models for Aircraft Wing Design Facilitating the Use of Dynamic Programming Approach
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作者 Prashant K. Tarun Herbert W. Corley 《American Journal of Operations Research》 2023年第5期111-131,共21页
Aircraft designers strive to achieve optimal weight-reliability tradeoffs while designing an aircraft. Since aircraft wing skins account for more than fifty percent of their structural weight, aircraft wings must be d... Aircraft designers strive to achieve optimal weight-reliability tradeoffs while designing an aircraft. Since aircraft wing skins account for more than fifty percent of their structural weight, aircraft wings must be designed with utmost care and attention in terms of material types and thickness configurations. In particular, the selection of thickness at each location of the aircraft wing skin is the most consequential task for aircraft designers. To accomplish this, we present discrete mathematical programming models to obtain optimal thicknesses either to minimize weight or to maximize reliability. We present theoretical results for the decomposition of these discrete mathematical programming models to reduce computer memory requirements and facilitate the use of dynamic programming for design purposes. In particular, a decomposed version of the weight minimization problem is solved for an aircraft wing with thirty locations (or panels) and fourteen thickness choices for each location to yield an optimal minimum weight design. 展开更多
关键词 Aircraft Wing Design Maximum Reliability Design Minimum Weight Design Dynamic Programming OPTIMIZATION DECOMPOSITION
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Weaving Wildlife Protection
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作者 CUI XIAOQIN 《ChinAfrica》 2023年第12期34-35,共2页
On 6 August,Zhou Guimei,a villager from Huangnan Village,Dadongba Town,Songyang County,Lishui City in east China’s Zhejiang Province,found a“strange bird”she had never seen before while washing clothes by a stream.... On 6 August,Zhou Guimei,a villager from Huangnan Village,Dadongba Town,Songyang County,Lishui City in east China’s Zhejiang Province,found a“strange bird”she had never seen before while washing clothes by a stream.She said the bird had green claws,big eyes,a sharp beak and white spots on its wings. 展开更多
关键词 VILLAGE SHARP WINGS
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WiNG节点仪器应用简介
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作者 吴青松 佴小君 +1 位作者 刘都让 付淼星 《物探装备》 2023年第5期299-302,306,共5页
WiNG节点仪器是Sercel公司的第三代节点仪器产品,具有轻便、续航时间长、无线实时质控、数据下载与充电一体化、数据管理软件操作简单、桩号自动拟合、RFID标签等特点;其无线质控有近距离的点对点直连,用于获取详细的节点运行状态数据... WiNG节点仪器是Sercel公司的第三代节点仪器产品,具有轻便、续航时间长、无线实时质控、数据下载与充电一体化、数据管理软件操作简单、桩号自动拟合、RFID标签等特点;其无线质控有近距离的点对点直连,用于获取详细的节点运行状态数据、运行测试、查看噪音等,和通过接力回传实现远距离节点站状态结果信息获取。2022年底国内首次引进该节点仪器系统并在中石化山东某三维地震勘探工区实施了大规模应用,取得了良好的应用效果。本文结合实际应用介绍了WiNG节点仪器的功能特点。 展开更多
关键词 地震勘探 节点仪器 WING 远程无线实时质控
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Structural Design and Analysis of Small Flapping Wing Aircraft Based on the Crank Slider Mechanism
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作者 Minghui Ma Fengli Liu Yongping Hao 《Journal of Electronic Research and Application》 2023年第1期25-31,共7页
In this project,the miniaturization of the aircraft was realized under the premise of strong maneuverability,high concealability,and driving a certain load,and the flight mode and structural characteristics of birds w... In this project,the miniaturization of the aircraft was realized under the premise of strong maneuverability,high concealability,and driving a certain load,and the flight mode and structural characteristics of birds were imitated.A small bionic flapping wing aircraft was built.The flapping of the wing was realized by the crank slider mechanism,and the sizes of each part were calculated according to the bionics formula.The wingspan was 360.37 mm,the body width was 22 mm,the body length was 300 mm,the wing area was 0.05 m^(2),the flapping amplitude was 71°.ADAMS software was used to simulate the dynamics of the designed aircraft,and the variation of flapping amplitude and angular velocity during the movement of the aircraft was obtained,which verified the feasibility of the mechanism.The prototype aircraft was made for flight test,and the designed bionic flapping wing aircraft achieved the expected effect.It provides a theoretical basis and data support for the design and manufacture of small flapping wing aircraft. 展开更多
关键词 Flapping wing aircraft Structural design Dynamic simulation
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Navigating Temporal and Spatial Dimensions:Unveiling the Fictional Essence and Authenticity in the Narrative of The Rise and Fall of Wing Shing Street
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作者 Xiaohan Lu Jing Yang 《Journal of Contemporary Educational Research》 2023年第11期6-10,共5页
The novel The Rise and Fall of Wing Shing Street delves into the reality of Hong Kong residents deeply attuned to spatial awareness but detached from temporal significance,entangling emotions surrounding time and spac... The novel The Rise and Fall of Wing Shing Street delves into the reality of Hong Kong residents deeply attuned to spatial awareness but detached from temporal significance,entangling emotions surrounding time and space.Through narrative interruption and extension,the author portrays the genuine struggles of Hong Kong inhabitants-juxtaposing the blurred boundaries of time and space and the inherent rootlessness of reality within a fictionalized framework.Emphasizing the 20th-century human condition,wherein spatial awareness overshadows temporal understanding,the novel underscores the consequences:a loss of history and cultural identity.With a fresh perspective,the narrative explores the interplay of time and space,accentuating both the fictitious and authentic dimensions.This prompts readers to reconsider their history,culture,and the current moment,ultimately highlighting the pivotal role of temporal awareness. 展开更多
关键词 The Rise and Fall of Wing Shing Street Spatial awareness Temporal awareness Rootlessness Cultural identity Return of the heart
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模糊WINGS视角下的ANP加权矩阵新构造方法 被引量:7
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作者 孙永河 李春好 +1 位作者 谢晖 段万春 《计算机工程与应用》 CSCD 2014年第12期26-32,37,共8页
构造因素集加权矩阵是ANP系统未加权超矩阵到加权超矩阵转化的一个关键技术。然而从已有的三种构造方法看,两两比较法比较机理混乱,而等权矩阵假设构造法通常是无效的,并且基于DEMATEL(决策试行与评价实验室)的构造方法不仅存在忽视因... 构造因素集加权矩阵是ANP系统未加权超矩阵到加权超矩阵转化的一个关键技术。然而从已有的三种构造方法看,两两比较法比较机理混乱,而等权矩阵假设构造法通常是无效的,并且基于DEMATEL(决策试行与评价实验室)的构造方法不仅存在忽视因素集自身强度的内在不足,而且也难以反映专家在对因素集之间影响关系判断时存在的"不精确性"。为克服上述缺陷,提出一种模糊WINGS(加权影响情景下的非线性测度体系)视角下的ANP因素集加权矩阵新构造方法。该方法一方面给出改进后的模糊DELPHI决策程序,充分考虑了专家判断过程中的"不精确性"。另一方面,系统提出模糊WINGS的方法思路,在系统因素集影响关系判别时充分考虑了因素集的自我影响强度,使因素集直接影响矩阵的构造更为合理。实例对比验证结果表明,该方法是科学合理的,有着较强的实践应用可操作性。 展开更多
关键词 模糊加权影响情景下的非线性测度体系(WINGS) 网络分析法 超矩阵 加权矩阵
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Paliurus(Paliureae,Rhamnaceae) from the Miocene of East China and its Macrofossil-based Phylogenetic and Phytogeographical History 被引量:5
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作者 LI Xiangchuan WANG Haofei +3 位作者 LENG Qin XIAO Liang GUO Junfeng HE Wenlong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第5期1364-1377,共14页
The extant genus Paliurus Miller is divided into P. ramosissimus and P. spina-christi groups and is diagnostically characterized by distinctive orbicular-winged fruits with a trilocular (or often bilocular) ovary an... The extant genus Paliurus Miller is divided into P. ramosissimus and P. spina-christi groups and is diagnostically characterized by distinctive orbicular-winged fruits with a trilocular (or often bilocular) ovary and basally triveined leaves with a subentire to serrate margin. Here, structurally preserved winged fruits and associated compressed leaves of Paliurus (Paliureae, Rhamnaceae) are reported from the Middle-Upper Miocene Shengxian Formation of Tiantai, Zhejiang, eastern China. The fruits can be identified as Paliurus microcarpa Xiang-Chuan Lisp. nov., the diagnostic characters of external morphology and anatomy of which differ from those of both extant and fossil generic members; the leaves can be designated as Paliurus sp. The species based on winged fruits, P. microcarpa, might represent an ancient intermediate link exclusively known across the P. ramosissimus and P. spina-christi groups, showing a closer affinity to the P. ramosissimus group based on the resemblant smaller fruits with a narrower wing, and to the P. spina-christi group based on the similar wing structure and texture, respectively. Morphological analyses of the present and previous fossil fruit records around the world indicate that diversification of Paliurus had begun in northern transpacific regions by the Late Eocene. The macrofossil records, i.e., fruits and leaves of Paliurus globally when projected on paleoenvironmental maps in view of changing continental positions through time (from Eocene to Miocene) display that the past distribution of the genus was much wider than the present and belongs to a tropical and warm temperate realm of the Northern Hemisphere. Therefore, the modern restricted disjunction in tropical and warm temperate regions of East Asia and South Europe (even eastwards West Asia) might represent glacial refugia for some of the generic ancient lineages to survive severe cold at least since the terminal Pliocene. 展开更多
关键词 PALEOBOTANY SYSTEMATICS Paliurus microcarpa winged fruit phytogeography Middle-LateMiocene Zhejiang Province
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百脉根侧部花瓣发育突变体的研究(英文) 被引量:1
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作者 王婕琛 田朝霞 +2 位作者 赵忠 罗达 胡筱荷 《分子植物育种》 CAS CSCD 2010年第1期6-10,共5页
为了研究调控花瓣形状发育的基因网络,我们在豆科模式植物百脉根中筛选影响侧部花瓣发育的突变体。我们鉴定了两个独立的突变体:kew2和kew3。这两个突变体有相似的表型:突变体的侧部花瓣转化为类似野生型的腹部花瓣。遗传分析表明kew3... 为了研究调控花瓣形状发育的基因网络,我们在豆科模式植物百脉根中筛选影响侧部花瓣发育的突变体。我们鉴定了两个独立的突变体:kew2和kew3。这两个突变体有相似的表型:突变体的侧部花瓣转化为类似野生型的腹部花瓣。遗传分析表明kew3和已报道的kew1等位,由同一个单隐性基因位点控制。kew1突变体定位于基因座位KEW1,与豌豆K位点直系同源。kew2的遗传分析暗示在侧部花瓣发育中有其它遗传因子与kew有相互作用。对这些突变体的分析和基因克隆有助于阐明两侧对称花型发育的调控机制和理解两侧对称花型的进化途径。 展开更多
关键词 百脉根 突变发生 Keeled—wing位点 花对称性
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新型的香豆素染料/碘鎓盐光敏引发系统的研究 被引量:1
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作者 高放 杨永源 《高分子学报》 SCIE CAS CSCD 北大核心 2000年第1期125-127,共3页
The photosensitive initiating system composed of 7 diethylamino 3 (2’ N methylbenzimidazolyl)coumarin dye (DBC) as sensitizer and diphenyliodonium hexafluorophosphate (DIH) as initiator,can be used to initiate the po... The photosensitive initiating system composed of 7 diethylamino 3 (2’ N methylbenzimidazolyl)coumarin dye (DBC) as sensitizer and diphenyliodonium hexafluorophosphate (DIH) as initiator,can be used to initiate the polymerization of methyl methacrylate (MMA) in visible light.When exposed to visible light,coumarin dye/iodonium salt undergoes quick electron transfer from DBC to DIH and free radicals are produced.The visible light photoinduced reaction between DBC and DIH is mainly through the excited singlet state of DBC and thus it is little sensitive to O 2.The fluorescence of DBC can be quenched efficiently by DIH and the change is in accord with Stern Volmer equation and the quench constant K q can reach 10 12 M -1 S -1 .The influence of concentration of DBC on the polymerization rate of MMA shows that coumarin free radical act mainly as chain terminator in polymerization and has a stronger tendency to terminate the chain reaction. 展开更多
关键词 染料敏化 光敏聚合 香豆素 碘Wing盐
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