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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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Molecular genetic diversity of winged bean gene pool in Thailand assessed by SSR markers 被引量:1
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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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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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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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Design of a Bio-inspired,Two-winged,Flapping-wing Micro Air Vehicle with High-lift Performance
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作者 Kai Hu Huichao Deng +2 位作者 Shengjie Xiao Gongyu Yang Yuhong Sun 《Journal of Bionic Engineering》 SCIE EI CSCD 2024年第3期1191-1207,共17页
In this paper,we present the development of our latest flapping-wing micro air vehicle(FW-MAV),named Explobird,which features two wings with a wingspan of 195 mm and weighs a mere 25.2 g,enabling it to accomplish vert... In this paper,we present the development of our latest flapping-wing micro air vehicle(FW-MAV),named Explobird,which features two wings with a wingspan of 195 mm and weighs a mere 25.2 g,enabling it to accomplish vertical take-off and hover flight.We devised a novel gear-based mechanism for the flapping system to achieve high lift capability and reliability and conducted extensive testing and analysis on the wings to optimise power matching and lift performance.The Explobird can deliver a peak lift-to-weight ratio of 1.472 and an endurance time of 259 s during hover flight powered by a single-cell LiPo battery.Considering the inherent instability of the prototype,we discuss the derivatives of its longitudinal system,underscoring the importance of feedback control,position of the centre of gravity,and increased damping.To demonstrate the effect of damping enhancement on stability,we also designed a passive stable FW-MAV.Currently,the vehicle is actively stabilised in roll by adjusting the wing root bars and in pitch through high-authority tail control,whereas yaw is passively stabilised.Through a series of flight tests,we successfully demonstrate that our prototype can perform vertical take-off and hover flight under wireless conditions.These promising results position the Explobird as a robust vehicle with high lift capability,paving the way towards the use of FW-MAVs for carrying load equipment in multiple tasks. 展开更多
关键词 Flapping wing Biologically inspired robots Mechanical design Flight dynamics Damping enhancement
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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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An adaptive machine learning-based optimization method in the aerodynamic analysis of a finite wing under various cruise conditions
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作者 Zilan Zhang Yu Ao +1 位作者 Shaofan Li Grace X.Gu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第1期27-34,共8页
Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight missions.Plenty of existing literature has considered two-dimensional infinite airfoil... Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight missions.Plenty of existing literature has considered two-dimensional infinite airfoil optimization,while three-dimensional finite wing optimizations are subject to limited study because of high computational costs.Here we create an adaptive optimization methodology built upon digitized wing shape deformation and deep learning algorithms,which enable the rapid formulation of finite wing designs for specific aerodynamic performance demands under different cruise conditions.This methodology unfolds in three stages:radial basis function interpolated wing generation,collection of inputs from computational fluid dynamics simulations,and deep neural network that constructs the surrogate model for the optimal wing configuration.It has been demonstrated that the proposed methodology can significantly reduce the computational cost of numerical simulations.It also has the potential to optimize various aerial vehicles undergoing different mission environments,loading conditions,and safety requirements. 展开更多
关键词 Aerodynamic optimization Computational fluid dynamics Radial basis function Finite wing Deep learning neural network
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Thrust Optimization of Flapping Wing via Gradient Descent Technologies
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作者 Jeshwanth Kundem 《Open Journal of Fluid Dynamics》 2024年第2期83-99,共17页
The current work aims at employing a gradient descent algorithm for optimizing the thrust of a flapping wing. An in-house solver has been employed, along with mesh movement methodologies to capture the dynamics of flo... The current work aims at employing a gradient descent algorithm for optimizing the thrust of a flapping wing. An in-house solver has been employed, along with mesh movement methodologies to capture the dynamics of flow around the airfoil. An efficient framework for implementing the coupled solver and optimization in a multicore environment has been implemented for the generation of optimized solutionsmaximizing thrust performance & computational speed. 展开更多
关键词 Steepest Descent CFD Flapping Wing Airfoil Thrust Performance
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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:5
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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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实现柔性机翼后缘形状变化的综合优化(英文) 被引量:10
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作者 刘世丽 葛文杰 李树军 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第2期187-192,共6页
Adaptive wings have long used smooth morphing technique of compliant leading and trailing edge to improve their aerodynamic characteristics. This paper introduces a systematic approach to design compliant structures t... Adaptive wings have long used smooth morphing technique of compliant leading and trailing edge to improve their aerodynamic characteristics. This paper introduces a systematic approach to design compliant structures to carry out required shape changes under distributed pressure loads. In order to minimize the deviation of the deformed shape from the target shape, this method uses MATLAB and ANSYS to optimize the distributed compliant mechanisms by way of the ground approach and genetic algorithm (GA) to remove the elements possessive of very low stresses. In the optimization process, many factors should be considered such as airloads, input displacements, and geometric nonlinearities. Direct search method is used to locally optimize the dimension and input displacement after the GA optimization. The resultant structure could make its shape change from 0 to 9.3 degrees. The experimental data of the model confirms the feasibility of this approach. 展开更多
关键词 adaptive wing compliant mechanism genetic algorithm topology optimization distributed pressure load geometric nonlinearity
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