scholarly journals Analysis of euphotic depth in snow with SNICAR transfer scheme

2017 ◽  
Vol 18 (12) ◽  
pp. 484-490
Author(s):  
Efang Zhong ◽  
Qian Li ◽  
Shufen Sun ◽  
Shangfeng Chen ◽  
Wen Chen
2013 ◽  
Vol 38 (3) ◽  
pp. 36-41
Author(s):  
Karen Di Franco

Since 2010, Book Works has been digitising material from its archive – whether finished works, ephemera, correspondence, photographs, or manuscripts – to give access to the working processes of the organisation (at www.bookworks.org.uk). The archive database is constructed around a chronological timeline and includes a search facility that allows visitors to filter and select material using a bespoke classification system. It currently comprises detailed content relating to two case studies from Book Works back catalogue: After the Freud Museum by Susan Hiller and Erasmus is late by Liam Gillick, as well as ephemera and material from other works. The project has been developed in collaboration with Ligatus Research Centre, University of the Arts London, with support from the AHRC Knowledge Transfer scheme.


2021 ◽  
Vol 32 (3) ◽  
Author(s):  
Dimitrios Bellos ◽  
Mark Basham ◽  
Tony Pridmore ◽  
Andrew P. French

AbstractOver recent years, many approaches have been proposed for the denoising or semantic segmentation of X-ray computed tomography (CT) scans. In most cases, high-quality CT reconstructions are used; however, such reconstructions are not always available. When the X-ray exposure time has to be limited, undersampled tomograms (in terms of their component projections) are attained. This low number of projections offers low-quality reconstructions that are difficult to segment. Here, we consider CT time-series (i.e. 4D data), where the limited time for capturing fast-occurring temporal events results in the time-series tomograms being necessarily undersampled. Fortunately, in these collections, it is common practice to obtain representative highly sampled tomograms before or after the time-critical portion of the experiment. In this paper, we propose an end-to-end network that can learn to denoise and segment the time-series’ undersampled CTs, by training with the earlier highly sampled representative CTs. Our single network can offer two desired outputs while only training once, with the denoised output improving the accuracy of the final segmentation. Our method is able to outperform state-of-the-art methods in the task of semantic segmentation and offer comparable results in regard to denoising. Additionally, we propose a knowledge transfer scheme using synthetic tomograms. This not only allows accurate segmentation and denoising using less real-world data, but also increases segmentation accuracy. Finally, we make our datasets, as well as the code, publicly available.


2020 ◽  
Vol 499 (1) ◽  
pp. 668-680
Author(s):  
Alejandro González-Samaniego ◽  
Enrique Vazquez-Semadeni

ABSTRACT We use two hydrodynamical simulations (with and without photoionizing feedback) of the self-consistent evolution of molecular clouds (MCs) undergoing global hierarchical collapse (GHC), to study the effect of the feedback on the structural and kinematic properties of the gas and the stellar clusters formed in the clouds. During this early stage, the evolution of the two simulations is very similar (implying that the feedback from low-mass stars does not affect the cloud-scale evolution significantly) and the star-forming region accretes faster than it can convert gas into stars, causing the instantaneous measured star formation efficiency (SFE) to remain low even in the absence of significant feedback. Afterwards, the ionizing feedback first destroys the filamentary supply to star-forming hubs and ultimately removes the gas from it, thus first reducing the star formation (SF) and finally halting it. The ionizing feedback also affects the initial kinematics and spatial distribution of the forming stars because the gas being dispersed continues to form stars, which inherit its motion. In the non-feedback simulation, the groups remain highly compact and do not mix, while in the run with feedback, the gas dispersal causes each group to expand, and the cluster expansion thus consists of the combined expansion of the groups. Most secondary star-forming sites around the main hub are also present in the non-feedback run, implying a primordial rather than triggered nature. We do find one example of a peripheral star-forming site that appears only in the feedback run, thus having a triggered origin. However, this appears to be the exception rather than the rule, although this may be an artefact of our simplified radiative transfer scheme.


2000 ◽  
Vol 143 (2) ◽  
pp. 407-410 ◽  
Author(s):  
Youlin Xia ◽  
Xiangming Kong ◽  
David K Smith ◽  
Yu Liu ◽  
David Man ◽  
...  

2019 ◽  
Vol 55 (1) ◽  
pp. 203-212
Author(s):  
Normann Fischer ◽  
Brian K. Johnson ◽  
Andrew G. Miles ◽  
Joseph D. Law

2008 ◽  
Vol 8 (1) ◽  
pp. 61-88 ◽  
Author(s):  
Gang Guo

This article examines local fiscal behavior in contemporary China against the backdrop of decentralized spending responsibilities and recentralized revenues. Vertical imbalance after the 1994 tax-sharing system reform, coupled with other features of the fiscal institutions, is not conducive to conservative local fiscal behavior. Moreover, a main driving force behind the expansion of local governments is the politically motivated intergovernmental transfer scheme. The center in effect “buys” political stability in sensitive areas while holding local leaders accountable for their tax efforts. A dynamic panel analysis of Chinese counties reveals that a million-yuan increase in general transfer payment and salary raise subsidies would add, respectively, fifteen and sixteen employees to the county government payroll, other things being equal. At the same time, increased subsidies from upper-level governments do not “crowd out” or significantly affect local tax effort. Additional dynamic panel data analysis at the provincial level produced similar findings.


1985 ◽  
Vol 4 (3) ◽  
pp. 93-98 ◽  
Author(s):  
T. P. C. Van Robbroeck

Most economic development in South Africa has taken place on the dry plateau of the interior following the discovery of minerals. The much smaller wetter parts get most of the run-off and have generally limited possibilities for advantageous use of their water resources. Consequently, it is logical to transfer water between basins with a surplus to ones experiencing shortages. There is a body of opinion that such transfers should be stopped in the interest of the decentralistion policy, but such action is not considered in the national interest. The intricate system of inter-basin transfer from the Komati, the Usutu and the Vaal River to supply the Eastern Transvaal coalfields is described. This system has shown its flexibility during the recent drought. The most important inter-basin transfer scheme is the Tugeia- Vaal Project which is described in broad terms. The advantages of the principle of reserve storage and of co-operation with Escom are dealt with. Possible further projects to augment the Vaal River supplies are mentioned. Other inter-basin transfer schemes implemented by the Department of Water Affairs such as the Orange River Project, the Riviersonderend-Berg River Project and others of lesser importance are dealth with.


2013 ◽  
Vol 10 (8) ◽  
pp. 13353-13398
Author(s):  
M. Mezbahuddin ◽  
R. F. Grant ◽  
T. Hirano

Abstract. Seasonal variation in water table depth (WTD) determines the balance between aggradation and degradation of tropical peatlands. Longer dry seasons together with human interventions (e.g. drainage) can cause WTD drawdowns making tropical peatland C storage highly vulnerable. Better predictive capacity for effects of WTD on net CO2 exchange is thus essential to guide conservation of tropical peat deposits. Mathematical modelling of basic eco-hydrological processes under site-specific conditions can provide such predictive capacity. We hereby deploy a mathematical model ecosys to study effects of seasonal variation in WTD on net ecosystem productivity (NEP) of an Indonesian peatland. We simulated lower NEPs (~ –2 g C m–2 d–1) during rainy seasons with shallow WTD, higher NEPs (~ +1 g C m–2 d–1) during early dry seasons with intermediate WTD and again lower NEPs (~ –4 g C mm–2 d–1) during late dry seasons with deep WTD during 2002–2005. These values were corroborated by regressions (P < 0.0001) of hourly modelled vs. eddy covariance (EC) measured net ecosystem CO2 fluxes which yielded R2 > 0.8, intercepts approaching 0 and slopes approaching 1. We also simulated a gradual increase in annual NEPs from 2002 (−609 g C m–2) to 2005 (−373 g C m–2) with decreasing WTD which was corroborated by EC-gap filled annual NEP estimates. These WTD effects on NEP were modelled from basic eco-hydrological processes including microbial and root oxidation-reduction reactions driven by soil and root O2 transport and uptake which in turn drove soil and plant C, N and P transformations within a soil-plant-atmosphere water transfer scheme driven by water potential gradients. This modelling should therefore provide a predictive capacity for WTD management programs to reduce tropical peat degradation.


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