Perfect transfer of coherent state-based qubits via coupled cavities

Motivated by the need for communication of coherent state-based qubits in quantum computers, we introduce a method for perfect transferring of an arbitrary superposition of coherent states between two distant nodes of a linear array of three semiconductor QDs. The QDs trapped in a system of coupled cavities. In this method, the field mode of the cavities, as the resource of transferring of quantum states, are only virtually excited which minimizes the effect of decoherence due to photon loss.Comment: 10 pages, 3 figures. arXiv admin note: text overlap with arXiv:quant-ph/0211055 by other author

Perfect routing of quantum information in regular cavity QED networks

We introduce a scheme for perfect routing of quantum states and entanglement in regular cavity QED networks. The couplings between the cavities are quasi-uniform and each cavity is doped with a two-level atom. Quasi-uniform couplings leads the system to evolve in invariant subspaces. Combination the evolutions of the system in its invariant subspaces with quite simple local operations on atoms in the networks, gives the perfect routing of quantum states and entanglement through the network. To provide the protocol be robust due to decoherence arisen from photon loss, the field mode of the cavities are only virtually excited

Study of existing biological communities in Hormuzgan province waters (Persian Gulf) for installation of artificial reefs

To determine the suitable locations for installation of artificial reefs we studied Persian Gulf waters (Hormuzgan province) from December 2006 to March 2007 seasonally. The area was stratified to 10 transects and each transect was divided to three layers and used random sampling method. Habitats of fauna and flora including: Communities of corals, seaweeds, sea cucumbers and sea grasses, and sedimentation depth using SCUBA diving method were studied in each transect and layer. Sea grass communities existed in some places with below 10m depth of Bandar Mesan, Bandar Kang, Kish Island and Bandar Chirooyeh transects. Also, seaweed habitats were seen in Bandar Mesan and some areas in Bandar Lengeh and Kish Island in 10-20m depth transect. The study of coral and sea cucumber communities indicated presence of Acropora sp. habitats in Bahman jetty, Bandar Mesan and Bandar Bostaneh transects , and Porites sp. habitats in Hengam island transect, Holothuria sp. habitats in Bandar masen and Bandar Lengeh transects and Stichopus sp. habitat in Hengam Island transect. All these species were found in shallow waters bellow 10 meters depth and showed a patchy distribution. Sedimentation depth results showed a statistically significant difference between layer <10m in Bandar Salakh and the same layers in other transects, also between layer 10-20m and 20-30m in other transects. Based on the sedimentation depth and habitats studies, we recommend layer 10-20m in Bandar Lengeh area and Bandar Lengeh to Hendurabi Island area as suitable for artificial reefs installation

Deriving a multi-subject functional-connectivity atlas to inform connectome estimation

MICCAI 2014 preprintInternational audienceThe estimation of functional connectivity structure from functional neuroimaging data is an important step toward understanding the mechanisms of various brain diseases and building relevant biomarkers. Yet, such inferences have to deal with the low signal-to-noise ratio and the paucity of the data. With at our disposal a steadily growing volume of publicly available neuroimaging data, it is however possible to improve the estimation procedures involved in connectome mapping. In this work, we propose a novel learning scheme for functional connectivity based on sparse Gaussian graphical models that aims at minimizing the bias induced by the regularization used in the estimation, by carefully separating the estimation of the model support from the coefficients. Moreover, our strategy makes it possible to include new data with a limited computational cost. We illustrate the physiological relevance of the learned prior, that can be identified as a functional connectivity atlas, based on an experiment on 46 subjects of the Human Connectome Dataset

Testing, FE modelling and design of pin-ended stainless steel equal-leg angle section columns and beam-columns

The behaviour and design of pin-ended stainless steel equal-leg angle section members under compression and compression plus minor-axis bending are investigated herein. The studied members are cylindrically pinned about the minor axis. An experimental investigation, including material testing, initial geometric imperfection measurements and physical tests on hot-rolled stainless steel equal-leg angle section members is first presented. Numerical models are developed and validated against the new experimental data. A numerical parametric study is then presented considering both hot-rolled and cold-formed stainless steel angle section columns alongside beam–columns with a wide range of slenderness values. Finally, new design proposals for pin-ended stainless steel equal-leg angle section members under compression and combined compression and minor-axis bending are developed and verified against the results of existing physical experiments, as well as the newly-generated test and numerical results. The proposed design rules are shown to offer substantially more accurate and consistent resistance predictions compared to existing codified design rules. The reliability of the new design provisions, with a recommended partial safety factor γM1 = 1.1, is verified following the EN 1990 procedure

New East Manchester: urban renaissance or urban opportunism?

In this paper we ask how a shrinking city responds when faced with a perforated urban fabric. Drawing on Manchester’s response to its perforated eastern flank - and informed by a parallel study of Leipzig - we use the city’s current approach to critique urban regeneration policy in England. Urban renaissance holds out the promise of delivering more sustainable - that is more compact, more inclusive and more equitable - cities. However, the Manchester study demonstrated that the attempt to stem population loss from the city is at best fragile, despite a raft of policies now in place to support urban renaissance in England. It is argued here that Manchester like Leipzig is likely to face an ongoing battle to attract residents back from their suburban hinterlands. This is especially true of the family market that we identify as being an important element for long-term sustainable population growth in both cities. We use the case of New East Manchester to consider how discourses linked to urban renaissance – particularly those that link urbanism with greater densities - rule out some of the options available to Leipzig, namely, managing the long-term perforation of the city. We demonstrate that while Manchester is inevitably committed to the urban renaissance agenda, in practice New East Manchester demonstrates a far more pragmatic – but equally unavoidable – approach. This we attribute to the gap between renaissance and regeneration described by Amin et al (2000) who define the former as urbanism for the middle class and the latter as urbanism for the working class. While this opportunistic approach may ultimately succeed in producing development on the ground, it will not address the fundamental, and chronic, problem; the combination of push and pull that sees families relocating to suburban areas. Thus, if existing communities in East Manchester are to have their area buoyed up – or sustained - by incomers, and especially families, with greater levels of social capital and higher incomes urban policy in England will have to be challenged

Active fixturing: literature review and future research directions

Fixtures are used to fixate, position and support workpieces and represent a crucial tool in manufacturing. Their performance determines the result of the whole manufacturing process of a product. There is a vast amount of research done on automatic fixture layout synthesis and optimisation and fixture design verification. Most of this work considers fixture mechanics to be static and the fixture elements to be passive. However, a new generation of fixtures has emerged that has actuated fixture elements for active control of the part–fixture system during manufacturing operations to increase the end product quality. This paper analyses the latest studies in the field of active fixture design and its relationship with flexible and reconfigurable fixturing systems. First, a brief introduction is given on the importance of research of fixturing systems. Secondly, the basics of workholding and fixture design are visited, after which the state-of-the-art in active fixturing and related concepts is presented. Fourthly, part–fixture dynamics and design strategies which take these into account are discussed. Fifthly, the control strategies used in active fixturing systems are examined. Finally, some final conclusions and prospective future research directions are presented

Study of biotic communities for artificial reef placement in Hormuzgan Province waters, the Persian Gulf

Persian Gulf waters (Hormuzgan Province) were studied from seasonally to determine the best locations for installation of artificial reefs. The area was stratified for 10 transects and each transect was divided into three stations: Station 1 for waters below 10m, station 2 for waters between 10 and 20m and station 3 for waters between 20 and 30m deep. Habitats of fauna and flora including communities of corals, seaweeds, sea cucumbers and sea grasses and sedimentation depth through scuba diving were studied in each transect and sub-transects. Sea grass communities existed in some spots within station 1 in Bandar Mesan, Bandar Lengeh, Kish Island and Bandar Chirooyeh transects, while for station 2, sea grasses were absent from Chirooyeh transect and present in Bandar Mesan, Bandar Kong and Kish Island transects. Also, seaweed habitats existed in station 1 in Bandar Mesan transect and some areas in Bandar Lengeh transect. Study of coral and sea cucumber communities indicated existence of Acropora sp. habitats in Bahman jetty, Bandar Mesan and Bandar Bostaneh transects, Porites sp. habitat in Hengam Island transect, Holothuria sp. habitats in Bandar Mesan and Bandar Lengeh transects and Stichopus sp. habitat in Hengam Island transect. All of these habitats were located in station 1 and had patchy distribution which was drawn in GIS software. Calculated sedimentation depth using degree scale in different transects demonstrated statistically significant differences between station 1 in Bandar Salakh transect and the same stations in other transects, also between station 2 and station 3 in other transects (P<0.05). The result of sedimentation depth assessment showed that station 2 in Bandar Lengeh area up to Hendurabi Island were better for artificial reefs installation compared to south of Gheshm Island with the exception of Bandar Kong and Bandar Chirooyeh transects

Connectivity-based parcellation of the human frontal polar cortex

The frontal pole corresponds to Brodmann area (BA) 10, the largest single architectonic area in the human frontal lobe. Generally, BA10 is thought to contain two or three subregions that subserve broad functions such as multitasking, social cognition, attention, and episodic memory. However, there is a substantial debate about the functional and structural heterogeneity of this large frontal region. Previous connectivity-based parcellation studies have identified two or three subregions in the human frontal pole. Here, we used diffusion tensor imaging to assess structural connectivity of BA10 in 35 healthy subjects and delineated subregions based on this connectivity. This allowed us to determine the correspondence of structurally based subregions with the scheme previously defined functionally. Three subregions could be defined in each subject. However, these three subregions were not spatially consistent between subjects. Therefore, we accepted a solution with two subregions that encompassed the lateral and medial frontal pole. We then examined resting-state functional connectivity of the two subregions and found significant differences between their connectivities. The medial cluster was connected to nodes of the default-mode network, which is implicated in internally focused, self-related thought, and social cognition. The lateral cluster was connected to nodes of the executive control network, associated with directed attention and working memory. These findings support the concept that there are two major anatomical subregions of the frontal pole related to differences in functional connectivity