Dove棱镜的加工误差对耦合损耗的影响

平行光束经过有加工误差的Dove棱镜后,在出射面往往会发生角度倾斜和离轴偏差,从而导致利用Dove棱镜制成的光纤旋转连接器的传输耦合损耗增大。对于Dove棱镜的加工误差在耦合损耗方面的影响,本文利用光线追迹的方法对其进行了理论及模拟分析。分析结果显示,由于加工误差带来的耦合损耗随着Dove棱镜的底角误差及其锥体角误差的增加而增大。而后依据理论结果及光纤旋转连接器的需求,设计加工了5块Dove棱镜,测量了其耦合损耗,并对实验测量值进行了修正,进一步验证了理论的正确性。

Morphometrics and Body Condition Index of Eurasian Collared-Dove and Mourning Dove in Durango, Mexico

In order to incorporate the knowledge of two species of wild doves and compare the results of both, we assessed morphometrics (body weight, bill, tarsus, tail, wing, head and culmen length) and body condition index (using weigh, wing, tail and tarsus length) of Eurasian Collared-Dove Streptopelia decaocto and Mourning Dove Zenaida macroura (Aves: Columbidae) based on 40 specimens of each species collected during fall-winter 2013 and spring-summer 2014 in the municipality of Durango, Durango, Mexico. We found that body condition index was higher during fallwinter for both species. We also found size dimorphism. Males of Eurasian Collared-Dove were larger than females in head length (p = 0.002) and tail length (p = 0.05) but smaller in culmen length. Female Mourning Doves had a higher body condition index compared to males (p = 0.02) during both seasons. As expected, Eurasian Collared-Dove was larger in all measurements than Mourning Dove (p > 0.05) but tail length (p = 0.12).

Progress of Chinese“Dove”and Future Studies on Flight Mechanism of Birds and Application System

This paper introduces the Chinese"Dove"——A practical application system of bird-mimetic air vehicles developed for more than a decade by the Institute of Flight Vehicle Innovation of Northwest Polytechnic University(NWPU)in China.Firstly,the main components,flight capability and flight verification of the Chinese"Dove"are presented.Then,the methods for the aerodynamic simulation and wind tunnel experiments are put forward.Secondly,the design of high-lift and high-thrust flexible flapping wings,a series of flapping mechanisms,gust-resistance layout and micro flight control/navigation system are presented.Some future studies on the application system of bionic micro air vehicles are given,including observation of natural flight creatures,aerodynamics in flight,mechanical and new material driving systems,structural mechanics,flight mechanics,and the information perception and intelligent decision-making control,which are related to research of flight bioinformatic perception and brain science.Finally,some application examples of complex flapping movements,active/passive deformation of bird wings,new low-energy motion-driven system,bionic intelligent decision-making and control/navigation are discussed.

Tolerance of disturbance by humans in long-time resident and recent colonist urban doves

Background: A critical trait for successful urban dwelling by birds is the ability to tolerate high levels of disturbing stimulation by humans. If such tolerance is partly acquired gradually after colonization, species with a long history of residence in cities are likely to be more tolerant of such stimulation than recent urban colonists, but this has not often been tested.Methods: We tested whether introduced Rock(Columba livia) and Spotted(Streptopelis chinensis) Doves, historically long-term residents of Melbourne, Australia, were more tolerant of disturbance by humans than the very recent colonist, the native Crested Pigeon(Ochyphaps lophotes) by comparing the Flight Initiation Distances(FID) and time allocations to vigilance during foraging of all three species in urban Melbourne. That all three species are members of the Columbiformes reduces the possibility that any species differences in tolerance are simply phylogenetic in origin.Results: Flight initiation distance was shorter in Rock Doves than in the other two species, which did not differ in approachability by a human. Rock Doves retreated from an approaching human mainly by walking a relatively short distance, Crested Pigeons mainly by running a relatively short distance and Spotted Doves primarily by flying a comparatively long distance. The time allocation to anti-predator vigilance of Rock Doves was smaller than that of the other two species, whose allocations were similar.Conclusions: The very recent colonist of eastern Melbourne, the Crested Pigeon, was not the least tolerant of disturbance by humans of the three related species. Natural selection for tolerance therefore probably cannot entirely explain the pattern of tolerance evident among these urban dove species and behavioural flexibility is probably involved. Length of residency in a city is not an infallible guide to a species' level of tolerance of disturbance by humans.

美国的职业教育相关数据(DOVE)系统

译者按:在美国的国家教育统计中心(National Center for Education Staustics)有一个职业教育相关数据系统(The Data on Vocational Education System).此系统的主要工作是收集有关职业教育的详尽数据,为国家制定职业教育政策提供依据.这个系统的重要性是不言而喻的,它记录下了美国职业教育发展的轨迹,为后人的研究提供了参考资料.本文由三个部分组成:DOVE系统的历史、DOVE系统简介和DOVE系统的完善.

Dove卫星高速数传技术分析

随着遥感卫星对地观测分辨率的提高,数据下传成为制约瓶颈,解决方法除了增加接收弧段和数据压缩比,提高传输速率是最有效的途径。Planet公司采用自己研制的5 kg量级卫星和4.5 m口径地面接收天线,在X数传频段的300 MHz带宽内实现了1.6 Gbit/s的信息传输速率。梳理了Planet数传系统的发展历程,对其原理进行了分析和计算,整理了地面站实际接收Dove卫星数传的统计数据,展现了Dove在Cubsat上实现1.6 Gbit/s速率的途径和结果,为遥感卫星高速数传的实现提供一种思路。

Hey mister Tambourine Dove, sing a song for me: simple but individually specific songs of Turtur tympanistria from Cameroon

Background: The broadcast song of the Tambourine Dove (Turtur tympanistria) is a repetitive coo series produced in a very stereotyped way. The song is similar to those of the other species within the Turtur genus and likely reflects the adaptation to long distance signalling in tropical habitats. There is no study assessing individual variation of the Tambourine Dove song or for the possibility of identity coding through song features. Methods: We obtained recordings of 578 songs from 41 males within a population inhabiting montane forest in Cameroon between 2008 and 2018. Additionally, we analysed also recordings from automatic recorders working for a longer time during the year. Songs were analysed to get basic information about within- and between-individual spectro-temporal variation. Potential of identity coding and discriminant analyses were used to investigate if and how these songs may convey information about male identity. Results: The song of the Tambourine Dove is a very simple series of short, unmodulated whistles with low frequency and a narrow bandwidth. Measurements of single song features indicated either none or a weak potential for identity coding. The overall variation in song frequency characteristics was very low. However, the number of notes forming a song (and consequently the duration) had a similar variability both within- and between individuals. When using multiple song measurements discrimination analysis revealed a high potential for identity coding although it seems that the temporal pattern of the beginning of a song carries the most information about sender identity. The production of initial notes within a song has very precise, individually specific timing allowing for up to 96.7% correct recognitions of songs. Comparison of recordings from the same points but separated in time by over a month indicates that song parameters are individually stable over longer period. Conclusions: Despite having highly stereotyped and simple songs, Tambourine Dove males produce individually specific signals which have a great potential for recognition by rivals or mates. All Turtur doves have similar yet unique songs that are different to the songs of other pigeon species. This genus seems to be a perfect model for studying the trade-off between coding for species identity and individual identity in a non-learning bird species. The described method of individual recognition allows for nonintrusive population monitoring.

The studies on neurogenesis induced by brain injury inadult ring dove

It was the first time demonstrated by us that the number of newborn neurons was increajsed after making lesion in forebraill of adult ring dove (Streptopelia risoria)by means of autoradiography and immunohistochemistry.Neurogenesis in the adult avian is restricted to the telencephalon. In doves with bilateral electrolytic lesion of nucleus ectostriatum (E), the mean number of proliferating cells in the lateral ventricular zone (LVZ) and newborn neurons in the forebrain increased by 1.95 times and 2.38times respectively as compared with that in intact doves. The most relllarkable increase of neurogenesis induced by nucleus ectostriatum lesions was found at the anteriorposterior level 3 (L3), where the lesion site was located.These results showed that the electrolytic brain lesion altered the distribution pattern of proliferating cells in theLVZ and resulted in increase of the number of newborn neurons in the non-VZ areas of forebrain. The changes in number and distribution pattern of proliferating cells in LVZ and newborn neurons in forebrain may be dependent on site of lesion. Studies on the relationship between proliferating cells in LVZ and newly generated neurons in non-VZ areas may help to understand the mechanism of brain plasticity and development.

Drivers of nest survival rate in a southern Tunisian population of Laughing Doves(Spilopelia senegalensis)

Background:Investigating the ecological factors and processes shaping nest survival is of great importance for assessing the breeding success of bird populations and understanding their spatio-temporal dynamics.Here,this question is addressed for the Laughing Dove(Spilopelia senegalensis),an expanding Afro-tropical bird in the Tunisian oasis habitat.Methods:This study took place in Kettana oasis,in south-eastern Tunisia.Natural Laughing Dove nests were searched for and monitored by means of regular visits,from the discovery date until the end of the breeding attempt(i.e.fledging or failure).Data were then used to investigate the relevance of laying date,nest age(days after clutch initiation),nest height and vegetation structure in the close nest tree environment as predictors of daily nest survival rate,using logistic-exposure models that accounted for heterogeneity in monitoring period among the studied nests.Models including different combinations of covariates were ranked according to their AICc scores,and the modelaveraging technique was used for the assessment of the effects of covariates on daily nest survival rate.Results:Vegetation structure in the close nest tree environment and nest age provided important predictors of daily nest survival rate,whereas neither nest height nor laying date showed significant effects.Daily nest survival rate was negatively associated with the presence of date palm trees in the close nest tree environment,but it was positively related to nest age.Daily nest survival rate was higher during the post-hatching stage than during the pre-hatching stage.Conclusions:Nests placed on fruit trees close to clumps of palm trees suffered higher predation risks compared to those placed on fruit trees situated far from palm trees.This is probably because palm tree clumps provided refuges for nest predators,notably the Black Rat(Rattus rattus)which has been reported to be the main nest predator in the oasis habitat.The predatory activity of this rodent seemed more directed against eggs than nestlings,which may explain the observed increase in daily survival rate with nest age.

Genetic diversity in Japanese populations of the Eurasian Collared Dove

Background:Eurasian Collared Dove(Streptopelia decaocto)is a species distributed in the Eurasian continent and North Africa,and inhabiting mainly in Saitama Prefecture in Japan.Eurasian Collared Dove is one of the most prosper-ous invaders in the world,and Japanese Eurasian Collared Dove has also been introduced from overseas.The Japa-nese population has declined to one-hundredth over 30 years and is being protected.In this study,we analyzed its genetic diversity in order to understand the genetic differences between wild populations of Eurasian Collared Dove and those bred in zoos.Methods:A sequence of about 1.9 kb mtDNA was determined for 20 wild Eurasian Collared Doves living in Saitama,Japan and 20 zoo-bred Eurasian Collared Doves,and population genetic analysis was performed.Results:In the COI gene,778 bp had the same sequence in all the 40 individuals examined,and no mutation sites could be confirmed.In the control region,two base substitution sites were confirmed in 1140 bp long sequence.Three haplotypes were detected in 20 individuals in wild,whereas all 20 zoo-bred individuals possessed the same haplotypes possessed in the wild population.Conclusion:Haplotypes of zoo-bred individuals were also retained among the wild individuals,confirming that no genetic problems could occur if the zoo-bred individuals were released to the wild for the Japanese Eurasian Collared Dove propagation program.

Analysis of Dove's Brand Communication Strategy in the Chinese Market

DOVE is one of the chocolate brands launched by MARS in China.For more than ten years since DOVE entered the Chinese market,she has continuously adjusted her marketing model to conform to the Chinese market and has become more and more popular with Chinese people.Her unique advertising model and fresh advertising style have formed a deeper brand impression in consumers’hearts generated by brand loyalty.This article mainly explores DOVE’s brand communication strategy in China from the marketing communication in DOVE’s overall brand marketing,and studies how DOVE,as a foreign brand,adapts to the local market and gains the first position in the market.DOVE serves as a leader for Chinese chocolate businesses to step out of difficulty and provideshelpful reference experience for China's multinational enterprises to survive in the context of global economy.

由“Lonesome Dove”一书译名的变化看社会发展对翻译的影响——从《西部牛仔情》到《孤独鸽》

翻译是一种跨语言和跨文化的行为 ,不同的文化背景、不同的社会意识形态都会对翻译产生影响。美国作家拉里·麦克默特里 (LarryMcMurtry)所著“LonesomeDove”一书 ,在 80年代后期曾被译为《西部牛仔情》 ,90年代后期 ,又被译为《孤独鸽》。该书在不同时期的不同译名 。

试论厄德里克小说《鸽灾》中的个人主义狂妄

个人主义的狂妄是美国殖民主义霸权的一个重要表征。本文以美国本土裔作家路易斯·厄德里克的小说《鸽灾》为蓝本,从理性的狂妄、实践利益的狂妄和鉴赏的狂妄三个极端个人主义的维度切入,深度透析在资本功利主义的驱使下,殖民者的狂妄偏执对人性的摧残,资本欲望的膨胀对人性扭曲和道德背离的催化,重申了音乐在精神救赎和创伤疗愈方面的重大作用,凸显了作者对原住民被消声了的小写历史的关切,对被删除了的历史记忆的愤懑和对当代美国殖民压迫的再思考。

基于高仿生形态布局的仿鸽扑翼飞行机器人系统设计

针对现有扑翼飞行机器人存在的飞行形态与实际鸟类相差较大,以及翅膀、尾翼布局和俯仰、转向控制方式仿生度较低的问题,提出一种形态布局与鸽子相仿的扑翼飞行机器人系统设计及实现方案.通过设计弧面-折翼-后掠翅膀、仿鸟扇形尾翼以及尾翼挨近翅膀后缘布置的布局方式,使扑翼机器人飞行形态更加接近真实鸟类,提高扑翼机器人的形态仿生度.在此基础上,设计结合下扑角调控无需尾翼大角度上翘的俯仰控制方式,以及不依赖于尾翼的翅膀收缩转向控制方式,在提高仿生度的同时保证飞行控制的有效性.在具体设计过程中,首先参考鸽子翅膀型式选择不同类型翅膀并进行风洞测试,确定出下扑角变化时仍能保持较优升推力性能的翅膀设计方案;其次,对各种尾翼型式进行分析和比较,结合鸽子尾翼特点进行仿鸽尾翼及俯仰、转向控制机构设计,并通过风洞测试验证;最后,设计飞控系统并装配整机,进行外场飞行测试,验证仿鸽扑翼飞行机器人平台的稳定性和可控性.

珙桐AP2/ERF家族相关基因的克隆及功能鉴定

为探究AP2/ERF类转录因子在珙桐开花调控及花器官发育中的作用,本研究通过从实验室珙桐不同发育时期苞片和叶片的转录组数据中筛选出调控珙桐苞片发育相关AP2/ERF家族基因DiAP2-1、DiDREB-1和DiRAV-1,经过生物信息学分析、基因克隆及功能鉴定初步研究了目的基因在珙桐苞片发育过程中的调控机制.亚细胞定位实验显示DiAP2-1主要定位于细胞质,DiDREB-1和DiRAV-1主要定位于细胞核.对目的基因在珙桐中的表达模式分析发现DiAP2-1和DiRAV-1在苞片发育过程中表达量逐渐降低,DiDREB-1只在苞片第三时期高表达,推测DiDREB-1、DiRAV-1属于A类基因,DiAP2-1属于B类基因.表型实验显示DiDREB-1和DiRAV-1转基因拟南芥株系较野生型表现为明显的早花,DiAP2-1同源基因对应的拟南芥突变体与同一时期野生型拟南芥对比表现为花瓣减少且萼片大,角果呈短粗状且败育.对关键开花调控基因表达模式分析发现DiDREB-1和DiRAV-1异源表达后使其他促花因子表达量上调进而使拟南芥花期提前.以上结果表明,AP2/ERF类转录因子DiAP2-1、DiDREB-1和DiRAV-1在珙桐苞片及花器官发育和珙桐开花调控中发挥了重要作用.

Dove Stewed with American Ginseng

Ingredients:Three doves, 10g American ginseng, 5g salt, 10g cookingwine, 30g scallion and ginger, 3g MSG, 2g white pepperpowder, 5g sesame oil arid 700g broth.Method:1. Cook the doves in boiling water for a short while, softenthe American ginseng in lukewarm water, then cut it intopieces;, mince the scallion and ginger.2. Put the doves into a clay pot, add broth, sliced Americanginseng and flavorings. Bring to the boil, then reduce heatand stew gently until the doves are tender. Remove fromheat and place on a flat plate. Sprinkle the sesame oil

Spatial games and the maintenance of cooperation in an asymmetric Hawk-Dove game

Classical theories explaining the evolution of cooperation often rely on the assumption that the involved players are symmetrically interacted.However,in reality almost all well-documented cooperation systems show that cooperative players are in fact asymmetrically interacted and that this dynamic may greatly affect the cooperative behavior of the involved players.Here,we developed several models based on the most well known spatial game of the Hawk-Dove game,while also considering the effects of asymmetric interaction.Such asymmetric games possess four kinds of strategies:cooperation or defection of strong player and cooperation or defection of weak player.Computer simulations showed that the probability of defection of the strong player decreases with decreasing the benefit to cost ratio,and that all kinds of strategy will be substituted by cooperation on behalf of the strong player if the benefit to cost ratio is sufficiently small.Moreover,weak players find it difficult to survive and the surviving weak players are mostly defectors,similar to the Boxed Pigs game.Interestingly,the patterns of kinds of strategies are chaotic or oscillate in some conditions with the related factors.

四手联弹的“四个四重奏”——《黑色维纳斯的诗艺人生与世界观照:丽塔·达夫研究》述评

王卓教授的专著《黑色维纳斯的诗艺人生与世界观照:丽塔·达夫研究》对美国当代著名非裔女诗人丽塔·达夫的创作进行了深入细致的研究。该著在总揽全貌的基础上,从横剖面切入,将诗人作品划分为成长书写、空间书写、历史书写、文化书写四大主题群,继而在每个主题群中又分出四个亚群,形成“四个四重奏”结构。身份建构、文化杂糅、对话叙事在四大主题的交汇处逐渐凝聚,生成诗人独特的诗学理念。王卓教授敏锐地捕捉到诗人的经验,并与之产生精神共鸣,可以看作重新定位、建构当代知识女性文化身份的跨时空对话,犹如四手联弹的艺术表演。该著可谓从宏观视角全局把握作品、将诗歌与诗学有机结合进行作家作品研究的范型。