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941.
This paper, which presents an annotated checklist of the ‘lower Nymphalidae’ (Libytheinae, Danainae, Satyrinae, Charaxinae), is the fourth in a series on the butterfly fauna of Mount Kilimanjaro. Four genera of lower Nymphalidae (Danaus, Amauris, Bicyclus, Charaxes), with a total of 11 included species, are known or believed to occur within the main forest zone, from c. 1800 to 2800 m. Of these, only three species of Charaxes (Charaxes berkeleyi, Charaxes ansorgei, Charaxes xiphares) may be restricted locally to this primary forest. The lower slopes fauna, below 1800 m, is considerably richer, with a total of 11 genera and 41 species listed (8 species of which extend into the forest zone). Possible additional species, dubious earlier records, problems with African subspecies of Danaus chrysippus, a need for more work on certain Satyrinae, and classification of the genus Charaxes are discussed. An identification key to the subfamilies of Nymphalidae, and the 19 genera of Libytheinae, Danainae, Satyrinae, Charaxinae that occur in Tanzania, together with a key to the adults of all the species of these four subfamilies considered to occur or have occurred on Kilimanjaro, with 206 colour images, are included as online Supplementary Information. 相似文献
942.
Sumaya Ahad 《Journal of Natural History》2016,50(27-28):1669-1685
One new and two known species of the genus Tantunema Siddiqi, 1982 are described and illustrated. Tantunema indicum sp. nov. is characterized by having a small body (length 0.32–0.45 mm); lip region cap-like, set off by slight constriction; odontostyle 6–7 µm and odontophore 8–10 µm long; pharyngeal expansion gradual, expanded part occupying about 35–41% of total neck length, lumen of posterior expanded part widened and thickened; female genital system mono-opisthodelphic, anterior genital branch absent; tail short, hemispheroid, 0.8–1.1 anal body diameter long. Tantunema pakistanense (Timm, 1964) comb. nov. (=Tylencholaimus pakistanensis Timm, 1964) and Tantunema intermedium (Peña-Santiago and Coomans, 1996) Andrássy, 2009 are redescribed. A diagnostic compendium and key to species of the genus is also provided. 相似文献
943.
Reconceptualising equilibrium in Boltzmannian statistical mechanics and characterising its existence
In Boltzmannian statistical mechanics macro-states supervene on micro-states. This leads to a partitioning of the state space of a system into regions of macroscopically indistinguishable micro-states. The largest of these regions is singled out as the equilibrium region of the system. What justifies this association? We review currently available answers to this question and find them wanting both for conceptual and for technical reasons. We propose a new conception of equilibrium and prove a mathematical theorem which establishes in full generality – i.e. without making any assumptions about the system׳s dynamics or the nature of the interactions between its components – that the equilibrium macro-region is the largest macro-region. We then turn to the question of the approach to equilibrium, of which there exists no satisfactory general answer so far. In our account, this question is replaced by the question when an equilibrium state exists. We prove another – again fully general – theorem providing necessary and sufficient conditions for the existence of an equilibrium state. This theorem changes the way in which the question of the approach to equilibrium should be discussed: rather than launching a search for a crucial factor (such as ergodicity or typicality), the focus should be on finding triplets of macro-variables, dynamical conditions, and effective state spaces that satisfy the conditions of the theorem. 相似文献
944.
《Journal of Natural History》2012,46(6):1413-1419
Didogobius schlieweni sp. nov. is described from a single specimen collected among pebbles in shallow water at Unije island, near Cres, in the northern Adriatic Sea. The holotype has vivid dark and pale patterning, and is assigned to Didogobius on the basis of head neuromast patterns and meristic features. Diagnostic values of the latter are D2 I/12, A I/11, P 17, and LL 55–56. A key to species of the Chromogobius and Didogobius complex is provided. 相似文献
945.
《Journal of Natural History》2012,46(6):1325-1331
A new genus of Conchaspididae, Asceloconchaspis gen. nov., is described for Asceloconchaspis milleri sp. nov., a new species from Florida, USA. Unlike other conchaspidids, the adult female and second instar of the genus lack legs. The presence of legs is one of the important, distinguishing characters at present separating the Conchaspididae from the Diaspididae. However, the new genus also possesses well-developed antennae and has multilocular disc pores on the abdomen in the adult female; these distinctly conchaspidid characters are never found in the Diaspididae. Asceloconchaspis is closely related to Fagisuga Lindinger, a monotypic genus with primitive characters described from South America on Nothofagus. A key to the four known genera of Conchaspididae is provided, and the morphology and distribution of the Conchaspididae are discussed. 相似文献
946.
《Journal of Natural History》2012,46(17-18):1079-1109
Ninety series of rhinotermitid termites were collected from 19 localities distributed across much of Thailand, and compared with specimens deposited in the NHML. Eleven species belonging to five genera of Rhinotermitidae are recorded from Thailand. Three species of two genera, Reticulitermes (Reticulitermes assamensis) and Parrhinotermes (Parrhinotermes microdentiformisoides and Parrhinotermes buttelreepeni), are new records from Thailand. Keys to the genera and species based on the soldier caste are given. Soldiers of all species are illustrated and morphological measurements are given. 相似文献
947.
针对武器装备体系贡献度评估中存在任务与能力关联复杂、数据处理缺乏有效性等问题,提出了基于置信规则推理的体系贡献度评估方法。首先,搭建了体系贡献度评估框架,通过使命分解和作战体系分析建立了“任务-能力”关联矩阵,并在此基础上构建了网络化多层次的评估指标体系。然后,利用基于置信规则推理的评估方法对体系作战效能进行推理。最后,根据体系贡献度评估模型计算武器装备体系贡献度。以空中遮断作战体系为例进行分析验证,结果表明该方法有效反映了体系的涌现性,客观评估了武器装备的体系贡献度,能够为装备迭代更新、作战体系发展规划提供理论支持。 相似文献
948.
I argue that we should consider Norton's material theory of induction as consisting of two largely independent claims. First, there is the claim that material facts license inductions - a claim which I interpret as a type of contextualism about induction. Second, there is the claim that there are no universal rules of induction. While a good case can be made for the first claim, I believe that Norton's arguments for the second claim are lacking. In particular, I spell out Norton's argument against the claim that all induction may be reduced to inference to the best explanation, and argue that it is not persuasive. Rejecting this part of Norton's theory does not however require us to abandon the first claim that material facts license inductions. In this way, I distinguish the parts of the material theory of induction we should happily accept from the parts about which we should be more skeptical. 相似文献
949.
ABSTRACTDuring the late Ming and early Qing period, Jesuit missionaries introduced European science into China, and thereby profoundly influenced the later development of Chinese astronomy. Not only did European astronomy become the official system of the Qing dynasty, but the traditional way to ‘attain up above’ by connecting the study of astronomy and Yi learning gradually fell into disuse. However, the astronomers in this period expressed different views on these two processes. As one of the most important early Qing astronomers, Xue Fengzuo’s case presents a distinctive and important example. Firstly, under the influences of both Chinese tradition and European science, Xue Fengzuo rebuilt the way to ‘attain up above’ based on his three-fold ‘calendrical learning’, i.e. calendrical astronomy, astrology and related pragmatic applications, through which he could realize the highest Confucian ideal. Secondly, he integrated Chinese and Western knowledge for all three aspects of his ‘calendrical learning’, instead of ceding the dominant position to Western methods. From Xue Fengzuo’s example, many of the complex effects of the encounter between different cultures and the process of knowledge transfer can be revealed. 相似文献
950.
单车场复杂情况下的车辆调度 总被引:4,自引:0,他引:4
针对单车场复杂情况下的车辆调度问题提出了一种改进的禁忌算法。该算法基于自然数编码,并且采用多初始解和全局禁忌表等技术,把不同的车型指标、路况信息、时间窗、容量、发车时间等约束通过控制车场插入和惩罚项加入到优化解中。本文介绍了此算法的原理,给出了具有代表性的算例试验结果和结果分析。实验表明,此方法对求解复杂情况下的车辆调度问题是有效的。 相似文献