扭n立方体中的边不交Hamilton圈

网络图的Hamilton性是图论、计算机网络理论中的重要研究议题，超立方体及其变体由于其良好的网络参数、拓扑结构吸引了众多学者的关注和研究，并将之广泛地应用于许多实际领域中．结合Lee距离Gray码理论证明了扭n方体中存在[n／2]个边不交Hamilton圈，并且给出这些边不交Hamilton圈的生成方法．     

一种适用于时序InSAR的同质像元加权干涉相位滤波方法

为了有效地利用多时相InSAR的时间维度信息, 并保证滤波窗口内像元的同质性, 提出一种同质像元加权干涉相位滤波方法。首先采用拟合优度检验, 对多时相SAR 图像的同质像元进行识别, 然后在同质像元之间进行加权干涉相位滤波, 以保证中心像元在滤波过程中不受周边非同质像元干扰。基于真实干涉SAR图像的实验结果表明, 与经典Goldstein滤波及Lee滤波相比, 该滤波方法在目视效果、相位残差点数量及相位导数标准差3个指标上具有优势, 实现滤波器的设计初衷。     

I ain’t afraid of no ghost

This paper criticizes the traditional philosophical account of the quantization of gauge theories and offers an alternative. On the received view, gauge theories resist quantization because they feature distinct mathematical representatives of the same physical state of affairs. This resistance is overcome by a sequence of ad hoc modifications, justified in part by reference to semiclassical electrodynamics. Among other things, these modifications introduce ”ghosts”: particles with unphysical properties which do not appear in asymptotic states and which are said to be purely a notational convenience. I argue that this sequence of modifications is unjustified and inadequate, making it a poor basis for the interpretation of ghosts. I then argue that gauge theories can be quantized by the same method as any other theory. On this account, ghosts are not purely notation: they are coordinates on the classical configuration space of the theory—specifically, on its gauge structure. This interpretation does not fall prey to the standard philosophical arguments against the significance of ghosts, due to Weingard. Weingard’s argumentative strategy, properly applied, in fact tells in favor of ghosts’ physical significance.     

Studies on induction hardening of powder-metallurgy-processed Fe-Cr/Mo alloys

Induction hardening of dense Fe-Cr/Mo alloys processed via the powder-metallurgy route was studied. The Fe-3Cr-0.5Mo, Fe-1.5Cr-0.2Mo, and Fe-0.85Mo pre-alloyed powders were mixed with 0.4wt%, 0.6wt%, and 0.8wt% C and compacted at 500, 600, and 700 MPa, respectively. The compacts were sintered at 1473 K for 1 h and then cooled at 6 K/min. Ferrite with pearlite was mostly observed in the sintered alloys with 0.4wt% C, whereas a carbide network was also present in the alloys with 0.8wt% C. Graphite at prior particle boundaries led to deterioration of the mechanical properties of alloys with 0.8wt% C, whereas no significant induction hardening was achieved in alloys with 0.4wt% C. Among the investigated samples, alloys with 0.6wt% C exhibited the highest strength and ductility and were found to be suitable for induction hardening. The hardening was carried out at a frequency of 2.0 kHz for 2-3 s. A case depth of 2.5 mm was achieved while maintaining the bulk (interior) hardness of approximately HV 230. A martensitic structure was observed on the outer periphery of the samples. The hardness varied from HV 600 to HV 375 from the sample surface to the interior of the case hardened region. The best combination of properties and hardening depth was achieved in case of the Fe-1.5Cr-0.2Mo alloy with 0.6wt% C.     

Guide for Authors

<正>The journal of"Progress in Natural Science:Materials International(PROG NAT SCI-MATER)"sponsored and organized by both Chinese Materials Research Society(C-MRS)and Inter national Union of Materials Research Societies(IUMRS)started to publish     

Whence the eigenstate–eigenvalue link?

David Wallace has recently argued that the eigenstate–eigenvalue (E–E) link has no place in serious discussions of quantum mechanics on the grounds that, as he claims, the E–E link is an invention of philosophers rather than the community of practicing physicists. This raises an historical question regarding the origin of the link. This paper aims to answer this question by tracing the historical development of the link through six key textbooks of quantum mechanics. In light of the historical evidence from these textbooks, it is argued that Wallace provides insufficient grounds for dismissing the E–E link from discussions of quantum mechanics.     

You are what you eat: native versus exotic Crotalaria species (Fabaceae) as host plants of the Ornate Bella Moth,Utetheisa ornatrix (Lepidoptera: Erebidae: Arctiinae)

Crotalaria plants and Utetheisa ornatrix are closely linked to each other: the larvae destroy the seeds, while the moth depends on hostplants for alkaloids. To better understand the ongoing co-evolution, the present study examines how native hostplants compare to exotic ones. Leaf-feeding on Crotalaria pumila, C. rotundifolia, and C. incana, native to the moth’s range, led to faster larval development than on the exotic C. lanceolata, C. spectabilis, and C. pallida. Seed-feeding on all species of Crotalaria led to accelerated larval development and a resultant larger adult moth, and correlates with a higher nitrogen content in the plant tissues. These results add a novel dimension to the previous studies of reproductive biology of this model organism. In controlled settings, mature larvae showed preference for leaves of C. spectabilis over those of other species, perhaps due to the higher alkaloid content. Differences in morphology and phenology of Crotalaria determine the ecology of U. ornatrix populations in Florida. The introduction of novel hostplants, on which U. ornatrix can have a significant negative effect and which are of concern to humans as invasive toxic weeds, has greatly expanded the niche occupied by this moth. Possible co-evolution of Utetheisa sensu lato and plant defences in the genus Crotalaria is discussed.     

Indirect and direct acoustic aggression in cicadas: first observations in the Palaearctic genus Tibicina Amyot (Hemiptera: Cicadomorpha: Cicadidae)

Tibicina Amyot is a cicada genus of the Palaearctic biogeographical region with seven taxa (species and subspecies) distributed in France. As in other cicadas, the sound production by tymbal vibration is restricted to males. In Tibicina, males are attracted by conspecific calling songs and tend to form groups of several individuals which maintain a minimal distance between each other. Observations based upon male–male interactions in such aggregations and on some preliminary experiments conducted with males kept in captivity revealed for the first time both indirect and direct aggression. Spacing and chorusing are interpreted as a by-product of indirect aggression mediated through the calling song. Direct aggression occurred when spacing is not respected. It is achieved through a ritualistic sequence that involves mainly the production of the rivalry song, an acoustic signal previously reported in the literature for two cicada species only. In addition, satellite males and male–male courting are reported. These preliminary results suggest that the sound social organization in the genus Tibicina is more elaborate than first suspected and should be reconsidered in terms of lek behaviour and sexual selection.     

A new feather mite genus of the family Psoroptoididae (Acari: Analgoidea) from cassowaries

A new feather mite genus Hexacaudalges gen. n. (Psoroptoididae: Psoroptoidinae) is established based on the type species Megninia casuaricola Proctor, 2001 Proctor, H. C. 2001. Megninia casuaricola sp. n. (Acari: Analgidae), the first feather mite from a cassowary (Aves: Struthioniformes: Casuariidae).. Australian Journal of Entomology, 40: 335–341. [Crossref], [Web of Science ®] , [Google Scholar], which was originally described from the southern cassowary Casuarius casuarius (Struthioniformes: Casuariidae). Morphological peculiarities of this genus, its taxonomic position within the family Psoroptoididae and possible origin are discussed. We also present a clarification of setal nomenclature for this family of mites.     

Radiolarians from the British North‐Polar Expedition (1875–1876): re‐examination of the H. B. Brady (1878) collection

The earliest report on radiolarians from the Arctic Ocean (north of the Arctic Circle) was provided by H. B. Brady (1878 Brady, H. B. 1878. On the reticularian and radiolarian Rhizopoda (Foraminifera and Polycystina) of the North‐Polar Expedition of 1875–76.. Annals and Magazine of Natural History, Series 5, 1: 425–440. [Taylor & Francis Online] , [Google Scholar]). He documented the occurrences of 10 genera from soundings in northern Baffin Bay and north of Greenland, but he did not illustrate any specimens in his report. We have re‐examined Brady's original slide collection, housed at the Natural History Museum, London (NHM), in order to refine his radiolarian identifications to species level. We have identified 11 radiolarian taxa in his slides, but some are definitely more characteristic of tropical oceans rather than high northern latitudes. We conclude that this is most likely due to sample contamination or misidentification of samples. Therefore, the actual occurrence of tropically affiliated radiolarians recorded from the Arctic is uncertain and should be regarded with suspicion.