Search results for "AAO"
showing 10 items of 40 documents
CCDC 149238: Experimental Crystal Structure Determination
2001
Related Article: S.Mahboobi, I.Dechant, H.Reindl, H.Pongratz, A.Popp, D.Schollmeyer|2000|J.Heterocycl.Chem.|37|307|doi:10.1002/jhet.5570370215
Sb2S3 nanovadu fotoelektriskās īpašības
2015
Perspektīvā nanovadus varēs izmantot sensoros, slēdžos, saules baterijās un citās optoelektriskajās ierīcēs, ņemot vērā to lielo virsmas un tilpuma attiecību. Pateicoties šai attiecībai, fizikālās īpašības nanoizmēros ir izteiktākas nekā makroskopiskos izmēros. Līdz šim nebija iespējams iegūt informāciju par Sb2S3 nanovadu fotoelektriskajām īpašībām. Darbā tika pētītas Sb2S3 nanovadu fotoelektriskās īpašības atkarībā no ierosinātās gaismas viļņu garuma, uzņemot I-V un fotostrāvas raksturlīknes. Darbā tika pētīta Sb2S3 nanovadu piemērotība dažādu optoelektrisko ierīču izstrādē. Anodētā alumīnija oksīda (AAO) matricā iekapsulēto nanovadu masīvu īpašības tika salīdzinātas ar individuālo nanova…
Ultraplānu anodizēta alumīnija oksīda saturošu daudzslāņu sistēmu iegūšana un optiskās īpašības
2015
Darba mērķis ir izveidot daudzslāņu sistēmas, kas satur anodētu alumīnija oksīdu, un raksturot to optiskās īpašības. Noteikts poru augšanas ātrums skābeņskābes un sērskābes elektrolītos. Analizēta membrānu biezuma, porainības, izmantotā metāla un putināšanas leņķa ietekme uz daudzslāņu sistēmas optiskajām īpašībām. Veikta paraugu kristalogrāfiskā analīze, raksturojot poru augšanu un sakārtotību dažādās kristalogrāfiskajās plaknēs. Izstrādātas metodes daudzslāņu sistēmas pārklāšanai ar fluorescentiem materiāliem.
Staging of osteonecrosis of the jaw requires computed tomography for accurate definition of the extent of bony disease
2014
AbstractManagement of osteonecrosis of the jaw associated with antiresorptive agents is challenging, and outcomes are unpredictable. The severity of disease is the main guide to management, and can help to predict prognosis. Most available staging systems for osteonecrosis, including the widely-used American Association of Oral and Maxillofacial Surgeons (AAOMS) system, classify severity on the basis of clinical and radiographic findings. However, clinical inspection and radiography are limited in their ability to identify the extent of necrotic bone disease compared with computed tomography (CT). We have organised a large multicentre retrospective study (known as MISSION) to investigate th…
Assessment of chronic aortic dissection: contribution of different ECG-gated breath-hold MRI techniques.
2004
Our objective was to evaluate the impact of different rapid MRI techniques for the assessment and follow-up of chronic aortic dissections.Fifty-three patients (41 postoperative Stanford type A, 12 type B dissections) were scanned at 1.5 T during a 3-year period. The study reviewed ECG-gated breath-hold black blood sequences and 3D contrast-enhanced MR angiography of the thoracic aorta supplemented by segmented cine and phase-contrast imaging as well as abdominal contrast-enhanced MR angiography. A retrospective separate analysis of black blood acquisitions and contrast-enhanced MR angiograms from a total of 72 examinations was performed by two radiologists to evaluate detection of intimal f…
Carcinoma of the neovagina: case report and review of the literature.
2001
Abstract Background. Carcinoma of the vagina is a rare disease, and it is even more rare in the neovagina. Nevertheless, it has been well described. The aim of this report was to analyze the reported cases and to add observations concerning a risk profile for this rare occurrence of carcinoma. Case report. The 29-year-old patient's history included congenital absence of vagina as a result of Rokitansky–Kuster syndrome. In 1987, when the patient was 17 years old, a neovagina was constructed by dissection between the bladder and the rectum, according to the Warthon method, and the apex of the neovagina was covered with Dura-mater. In 1990 the patient underwent radiation treatment with brachyt…
Counterexamples to the Kalman Conjectures
2018
In the paper counterexamples to the Kalman conjecture with smooth nonlinearity basing on the Fitts system, that are periodic solution or hidden chaotic attractor are presented. It is shown, that despite the fact that Kalman’s conjecture (as well as Aizerman’s) turned out to be incorrect in the case of n > 3, it had a huge impact on the theory of absolute stability, namely, the selection of the class of nonlinear systems whose stability can be studied with linear methods. peerReviewed
Hidden and self-excited attractors in radiophysical and biophysical models
2017
One of the central tasks of investigation of dynamical systems is the problem of analysis of the steady (limiting) behavior of the system after the completion of transient processes, i.e., the problem of localization and analysis of attractors (bounded sets of states of the system to which the system tends after transient processes from close initial states). Transition of the system with initial conditions from the vicinity of stationary state to an attractor corresponds to the case of a self-excited attractor. However, there exist attractors of another type: hidden attractors are attractors with the basin of attraction which does not have intersection with a small neighborhoods of any equ…
Impact of chaotic dynamics on the performance of metaheuristic optimization algorithms : An experimental analysis
2022
Random mechanisms including mutations are an internal part of evolutionary algorithms, which are based on the fundamental ideas of Darwin's theory of evolution as well as Mendel's theory of genetic heritage. In this paper, we debate whether pseudo-random processes are needed for evolutionary algorithms or whether deterministic chaos, which is not a random process, can be suitably used instead. Specifically, we compare the performance of 10 evolutionary algorithms driven by chaotic dynamics and pseudo-random number generators using chaotic processes as a comparative study. In this study, the logistic equation is employed for generating periodical sequences of different lengths, which are use…
Approximating hidden chaotic attractors via parameter switching.
2018
In this paper, the problem of approximating hidden chaotic attractors of a general class of nonlinear systems is investigated. The parameter switching (PS) algorithm is utilized, which switches the control parameter within a given set of values with the initial value problem numerically solved. The PS-generated attractor approximates the attractor obtained by averaging the control parameter with the switched values, which represents the hidden chaotic attractor. The hidden chaotic attractors of a generalized Lorenz system and the Rabinovich-Fabrikant system are simulated for illustration. In Refs. 1–3, it is proved that the attractors of a chaotic system, considered as the unique numerical …