scholarly journals Online Dominant Generalized Eigenvectors Extraction Via A Randomized Method

2021 ◽  
Author(s):  
Haoyuan Cai ◽  
Maboud F. Kaloorazi ◽  
Jie Chen ◽  
Wei Chen ◽  
Cedric Richard
Keyword(s):  
Generalized Eigenvectors ◽  
Randomized Method

scholarly journals Transpancreatic biliary sphincterotomy versus double guidewire in difficult biliary cannulation: a randomized controlled trial

Endoscopy ◽  
2021 ◽  
Author(s):  
Leena Kylänpää ◽  
Vilja Koskensalo ◽  
Arto Saarela ◽  
Per Ejstrud ◽  
Marianne Udd ◽  
...  
Keyword(s):  
Pancreatic Duct ◽  
Controlled Trial ◽  
Good Alternative ◽  
Endoscopic Retrograde ◽  
Biliary Cannulation ◽  
Randomized Controlled ◽  
Biliary Sphincterotomy ◽  
Difficult Biliary Cannulation ◽  
Definition Of ◽  
Randomized Method

Abstract Background Difficult biliary cannulation in endoscopic retrograde cholangiopancreatography (ERCP) increases the risk of post-ERCP pancreatitis (PEP). The purpose of this prospective, randomized, multicenter study was to compare two advanced rescue methods, transpancreatic biliary sphincterotomy (TPBS) and a double-guidewire (DGW) technique, in difficult common bile duct (CBD) cannulation. Methods Patients with native papilla and planned CBD cannulation were recruited at eight Scandinavian hospitals. An experienced endoscopist attempted CBD cannulation with wire-guided cannulation. If the procedure fulfilled the definition of difficult cannulation and a guidewire entered the pancreatic duct, randomization to either TPBS or to DGW was performed. If the randomized method failed, any method available was performed. The primary end point was the frequency of PEP and the secondary end points included successful cannulation with the randomized method. Results In total, 1190 patients were recruited and 203 (17.1 %) were randomized according to the study protocol (TPBS 104 and DGW 99). PEP developed in 14/104 patients (13.5 %) in the TPBS group and 16/99 patients (16.2 %) in the DGW group (P = 0.69). No difference existed in PEP severity between the groups. The rate of successful deep biliary cannulation was significantly higher with TPBS (84.6 % [88/104]) than with DGW (69.7 % [69/99]; P = 0.01). Conclusions In difficult biliary cannulation, there was no difference in PEP rate between TPBS and DGW techniques. TPBS is a good alternative in cases of difficult cannulation when the guidewire is in the pancreatic duct.

Entropy-Randomized Method for the Reconstruction of Missing Data

2021 ◽  
Vol 82 (4) ◽  
pp. 670-686
Author(s):  
Yu. A. Dubnov ◽  
V. Yu. Polishchuk ◽  
Yu. S. Popkov ◽  
Yu. M. Polishchuk ◽  
A. V. Mel’nikov ◽  
...  
Keyword(s):  
Missing Data ◽  
Randomized Method

scholarly journals Spectral analysis of a class of hermitian Jacobi matrices in a critical (double root) hyperbolic case

2010 ◽  
Vol 53 (1) ◽  
pp. 239-254 ◽  
Author(s):  
Serguei Naboko ◽  
Sergey Simonov
Keyword(s):  
Spectral Analysis ◽  
Jacobi Matrices ◽  
Double Root ◽  
Full Generality ◽  
Hyperbolic Case ◽  
Generalized Eigenvectors

AbstractWe consider a class of Jacobi matrices with periodically modulated diagonal in a critical hyperbolic (‘double root’) situation. For the model with ‘non-smooth’ matrix entries we obtain the asymptotics of generalized eigenvectors and analyse the spectrum. In addition, we reformulate a very helpful theorem from a paper by Janas and Moszynski in its full generality in order to serve the needs of our method.

scholarly journals Riesz basis property of Timoshenko beams with boundary feedback control

2003 ◽  
Vol 2003 (28) ◽  
pp. 1807-1820 ◽  
Author(s):  
De-Xing Feng ◽  
Gen-Qi Xu ◽  
Siu-Pang Yung
Keyword(s):  
Feedback Control ◽  
Riesz Basis ◽  
Closed Loop ◽  
Loop System ◽  
Beam Equation ◽  
Closed Loop System ◽  
Boundary Feedback Control ◽  
Riesz Basis Property ◽  
Boundary Feedback ◽  
Generalized Eigenvectors

A Timoshenko beam equation with boundary feedback control is considered. By an abstract result on the Riesz basis generation for the discrete operators in the Hilbert spaces, we show that the closed-loop system is a Riesz system, that is, the sequence of generalized eigenvectors of the closed-loop system forms a Riesz basis in the state Hilbert space.

scholarly journals GENERALIZED EIGENVECTORS FOR RESONANCES IN THE FRIEDRICHS MODEL AND THEIR ASSOCIATED GAMOV VECTORS

2006 ◽  
Vol 18 (01) ◽  
pp. 61-78 ◽  
Author(s):  
HELLMUT BAUMGÄRTEL
Keyword(s):  
Hardy Space ◽  
Half Plane ◽  
Lower Half Plane ◽  
Linear Forms ◽  
Generalized Eigenvalues ◽  
Dirac Type ◽  
Generalized Eigenvectors ◽  
Upper Half Plane ◽  
Friedrichs Model ◽  
Generalized Eigenvector

A Gelfand triplet for the Hamiltonian H of the Friedrichs model on ℝ with multiplicity space [Formula: see text], [Formula: see text], is constructed such that exactly the resonances (poles of the inverse of the Livšic-matrix) are (generalized) eigenvalues of H. The corresponding eigen(anti)linear forms are calculated explicitly. Using the wave matrices for the wave (Möller) operators the corresponding eigen(anti)linear forms on the Schwartz space [Formula: see text] for the unperturbed Hamiltonian H0 are also calculated. It turns out that they are of pure Dirac type and can be characterized by their corresponding Gamov vector λ → k/(ζ0 - λ)-1, ζ0 resonance, [Formula: see text], which is uniquely determined by restriction of [Formula: see text] to [Formula: see text], where [Formula: see text] denotes the Hardy space of the upper half-plane. Simultaneously this restriction yields a truncation of the generalized evolution to the well-known decay semigroup for t ≥ 0 of the Toeplitz type on [Formula: see text]. That is: Exactly those pre-Gamov vectors λ → k/(ζ - λ)-1, ζ from the lower half-plane, [Formula: see text], have an extension to a generalized eigenvector of H if ζ is a resonance and if k is from that subspace of [Formula: see text] which is uniquely determined by its corresponding Dirac type antilinear form.

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