scholarly journals EoR imaging with the SKA: the challenge of foreground removal

2017 ◽  
Vol 12 (S333) ◽  
pp. 269-273
Author(s):  
Anna Bonaldi

Abstract21-cm observations of the Cosmic dawn (CD) and Epoch of Reionization (EoR) are one of the high priority science objectives for SKA Low. One of the most difficult aspects of the 21-cm measurement is the presence of foreground emission, due to our Galaxy and extragalactic sources, which is about four orders of magnitude brighter than the cosmological signal. While end-to-end simulations are being produced to investigate in details the foreground subtraction strategy, it is useful to complement this thorough but time-consuming approach with simpler, quicker ways to evaluate performance and identify possible critical steps. In this work, I present a forecast method, based on Bonaldi et al. (2015), Bonaldi & Ricciardi (2011), to understand the level of residual contamination after a component separation step, and its impact on our ability to investigate CD and EoR.

2016 ◽  
Vol 222 (1) ◽  
pp. 3 ◽  
Author(s):  
Le Zhang ◽  
Emory F. Bunn ◽  
Ata Karakci ◽  
Andrei Korotkov ◽  
P. M. Sutter ◽  
...  

2017 ◽  
Vol 12 (S333) ◽  
pp. 77-82
Author(s):  
Rachel L. Webster ◽  

AbstractThe MWA EoR is one of a small handful of experiments designed to detect the statistical signal from the Epoch of Reionisation. Each of these experiments has reached a level of maturity, where the challenges, in particular of foreground removal, are being more fully understood. Over the past decade, the MWA EoR Collaboration has developed expertise and an understanding of the elements of the telescope array, the end-to-end pipelines, ionospheric conditions, and and the foreground emissions. Sufficient data has been collected to detect the theoretically predicted EoR signal. Limits have been published regularly, however we still several orders of magnitude from a possible detection. This paper outlines recent progress and indicates directions for future efforts.


VASA ◽  
2016 ◽  
Vol 45 (3) ◽  
pp. 223-228 ◽  
Author(s):  
Jan Paweł Skóra ◽  
Jacek Kurcz ◽  
Krzysztof Korta ◽  
Przemysław Szyber ◽  
Tadeusz Andrzej Dorobisz ◽  
...  

Abstract. Background: We present the methods and results of the surgical management of extracranial carotid artery aneurysms (ECCA). Postoperative complications including early and late neurological events were analysed. Correlation between reconstruction techniques and morphology of ECCA was assessed in this retrospective study. Patients and methods: In total, 32 reconstructions of ECCA were performed in 31 symptomatic patients with a mean age of 59.2 (range 33 - 84) years. The causes of ECCA were divided among atherosclerosis (n = 25; 78.1 %), previous carotid endarterectomy with Dacron patch (n = 4; 12.5 %), iatrogenic injury (n = 2; 6.3 %) and infection (n = 1; 3.1 %). In 23 cases, intervention consisted of carotid bypass. Aneurysmectomy with end-to-end suture was performed in 4 cases. Aneurysmal resection with patching was done in 2 cases and aneurysmorrhaphy without patching in another 2 cases. In 1 case, ligature of the internal carotid artery (ICA) was required. Results: Technical success defined as the preservation of ICA patency was achieved in 31 cases (96.9 %). There was one perioperative death due to major stroke (3.1 %). Two cases of minor stroke occurred in the 30-day observation period (6.3 %). Three patients had a transient hypoglossal nerve palsy that subsided spontaneously (9.4 %). At a mean long-term follow-up of 68 months, there were no major or minor ipsilateral strokes or surgery-related deaths reported. In all 30 surviving patients (96.9 %), long-term clinical outcomes were free from ipsilateral neurological symptoms. Conclusions: Open surgery is a relatively safe method in the therapy of ECCA. Surgical repair of ECCAs can be associated with an acceptable major stroke rate and moderate minor stroke rate. Complication-free long-term outcomes can be achieved in as many as 96.9 % of patients. Aneurysmectomy with end-to-end anastomosis or bypass surgery can be implemented during open repair of ECCA.


Author(s):  
Ahmed Mousa ◽  
Ossama M. Zakaria ◽  
Mai A. Elkalla ◽  
Lotfy A. Abdelsattar ◽  
Hamad Al-Game'a

AbstractThis study was aimed to evaluate different management modalities for peripheral vascular trauma in children, with the aid of the Mangled Extremity Severity Score (MESS). A single-center retrospective analysis took place between 2010 and 2017 at University Hospitals, having emergencies and critical care centers. Different types of vascular repair were adopted by skillful vascular experts and highly trained pediatric surgeons. Patients were divided into three different age groups. Group I included those children between 5 and 10 years; group II involved pediatrics between 11 and 15 years; while children between 16 and 21 years participated in group III. We recruited 183 children with peripheral vascular injuries. They were 87% males and 13% females, with the mean age of 14.72 ± 04. Arteriorrhaphy was performed in 32%; end-to-end anastomosis and natural vein graft were adopted in 40.5 and 49%, respectively. On the other hand, 10.5% underwent bypass surgery. The age groups I and II are highly susceptible to penetrating trauma (p = 0.001), while patients with an extreme age (i.e., group III) are more susceptible to blunt injury (p = 0.001). The MESS has a significant correlation to both age groups I and II (p = 0.001). Vein patch angioplasty and end-to-end primary repair should be adopted as the main treatment options for the repair of extremity vascular injuries in children. Moreover, other treatment modalities, such as repair with autologous vein graft/bypass surgery, may be adopted whenever possible. They are cost-effective, reliable, and simple techniques with fewer postoperative complication, especially in poor/limited resources.


2014 ◽  
Vol 1 (1) ◽  
pp. 9-34
Author(s):  
Bobby Suryajaya

SKK Migas plans to apply end-to-end security based on Web Services Security (WS-Security) for Sistem Operasi Terpadu (SOT). However, there are no prototype or simulation results that can support the plan that has already been communicated to many parties. This paper proposes an experiment that performs PRODML data transfer using WS-Security by altering the WSDL to include encryption and digital signature. The experiment utilizes SoapUI, and successfully loaded PRODML WSDL that had been altered with WSP-Policy based on X.509 to transfer a SOAP message.


1982 ◽  
Vol 136 (2) ◽  
pp. 347
Author(s):  
V.I. Kostenko ◽  
L.I. Matveenko ◽  
I.G. Moiseev

Controlling ◽  
2019 ◽  
Vol 31 (6) ◽  
pp. 63-65
Author(s):  
Carsten Speckmann ◽  
Péter Horváth

MindSphere ist das cloudbasierte, offene IoT-Betriebssystem von Siemens. Es verbindet Produkte, Anlagen, Systeme und Maschinen und ermöglicht es so, die Fülle von Daten aus dem Internet der Dinge (IoT) mit umfangreichen Analysen zu nutzen. Als eine sichere, skalierbare End-to-End-Lösung für die Industrie sorgt MindSphere für die Konnektivität von Anlagen und liefert somit handlungsrelevante Geschäftserkenntnisse, die zur Steigerung der Produktivität und Effizienz im gesamten Unternehmen nutzbar gemacht werden können. MindSphere ist weltweit verfügbar.


2018 ◽  
Vol E101.B (11) ◽  
pp. 2267-2276 ◽  
Author(s):  
Yoshihiko UEMATSU ◽  
Shohei KAMAMURA ◽  
Hiroshi YAMAMOTO ◽  
Aki FUKUDA ◽  
Rie HAYASHI

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