Model reference adaptive backstepping control of double star induction machine with extended Kalman sensorless control

Introduction. Newly, the design of a controller for speed control of double star induction motor as a research focus. Consequently, backstepping technique is used to recursively construct a stable control law for speed and flux. Nevertheless, this control law coming from backstepping requires the knowledge of speed and flux values; in practice the measurement sensors are expensive and fragile. The novelty of this work consists to propose a control strategy which based on accurate Kalman filter observer that estimates speed, flux and torque. This extended Kalman filter is an optimal state estimator and is usually applied to a dynamic system that involves a random noise environment. Purpose. Apply a backstepping control of double star induction motor based on principle of rotor flux orientation. This approach consists in finding a Lyapunov function that allows deducing a control law and a modified adaptation rule is referred and sufficient conditions for the stability of the command-observer, in contrast to other techniques who use nonlinear principle. Results. The simulation results are shown to illustrate the performance of the proposed scheme under parametric uncertainties by simulation on MATLAB. The obtained results showed the robustness of the sensorless control in front of load and parameters variation of double stator induction motor. The research directions of the model were determined for the subsequent implementation of results with simulation samples.Вступ. Новітня розробка контролера для регулювання швидкості асинхронного двигуна з подвійною зіркою є предметом дослідження. Отже, метод відступу використовується для рекурсивної побудови стабільного закону керування швидкістю та потоком. Тим не менш, цей закон керування, що випливає з відступу, вимагає знання значення швидкості та потоку; на практиці вимірювальні датчики коштовні та недовговічні. Новизна даної роботи полягає в тому, щоб запропонувати стратегію управління на основі точного спостерігача за фільтром Калмана, який оцінює швидкість, потік і крутний момент. Цей розширений фільтр Калмана є оптимальним засобом оцінки стану і зазвичай застосовується до динамічної системи, яка включає середовище випадкових шумів. Мета. Застосування підходу відступу до керування асинхронним двигуном з подвійною зіркою на основі принципу орієнтації потоку ротора. Цей підхід полягає у знаходженні функції Ляпунова, яка дозволяє вивести закон керування та модифіковане правило адаптації, а також достатні умови для стабільності спостерігача команд, на відміну від інших методик, які використовують нелінійний принцип. Результати. Результати моделювання наведені для ілюстрації роботи запропонованої схеми за параметричних невизначеностей шляхом моделювання на MATLAB. Отримані результати показали надійність безсенсорного керування перед зміною навантаження та параметрів асинхронного двигуна з подвійним статором. Визначені напрямки дослідження моделі для подальшої реалізації результатів на прикладах моделювання

Two Dimensional Fractional Supersymmetry from the Quantum Poincare Group at Roots of Unity

A group theoretical understanding of the two dimensional fractional supersymmetry is given in terms of the quantum Poincare group at roots of unity. The fractional supersymmetry algebra and the quantum group dual to it are presented and the pseudo-unitary, irreducible representations of them are obtained. The matrix elements of these representations are explicitly constructed.Comment: 10 pages. Some misprints are corrected. To appear in J. Phys.

Brain-vascular segmentation for SEEG planning via a 3D fully-convolutional neural network

Three dimensional visualization of vascular structures can assist clinicians in preoperative planning, intra-operative guidance, and post-operative decision-making. The goal of this work is to provide an automatic, accurate and fast method for brain vessels segmentation in Contrast Enhanced Cone Beam Computed Tomography (CE-CBCT) dataset based on a residual Fully Convolutional Neural Network (FCNN). The proposed NN embeds in an encoder-decoder architecture residual elements which decreases the vanishing effect due to deep architecture while accelerating the convergence. Moreover, a two-stage training has been proposed as a countermeasure for the unbalanced nature of the dataset. The FCNN training was performed on 20 CE-CBCT volumes exploiting mini-batch gradient descent andthe Adam optimizer. Binary cross-entropy was used as loss function. Performance evaluation was conducted considering 5 datasets. A median value of Dice, Precision and Recall of 0.79, 0.8 and 0.69 were obtained with respect to manual annotations

The osteoporosis treatment gap in patients at risk of fracture in European primary care : a multi-country cross-sectional observational study

Summary This study in 8 countries across Europe found that about 75% of elderly women seen in primary care who were at high risk of osteoporosis-related fractures were not receiving appropriate medication. Lack of osteoporosis diagnosis appeared to be an important contributing factor. Introduction Treatment rates in osteoporosis are documented to be low. We wished to assess the osteoporosis treatment gap in women ≥ 70 years in routine primary care across Europe. Methods This cross-sectional observational study in 8 European countries collected data from women 70 years or older visiting their general practitioner. The primary outcome was treatment gap: the proportion who were not receiving any osteoporosis medication among those at increased risk of fragility fracture (using history of fracture, 10-year probability of fracture above country-specific Fracture Risk Assessment Tool [FRAX] thresholds, T-score ≤ − 2.5). Results Median 10-year probability of fracture (without bone mineral density [BMD]) for the 3798 enrolled patients was 7.2% (hip) and 16.6% (major osteoporotic). Overall, 2077 women (55%) met one or more definitions for increased risk of fragility fracture: 1200 had a prior fracture, 1814 exceeded the FRAX threshold, and 318 had a T-score ≤ − 2.5 (only 944 received a dual-energy x-ray absorptiometry [DXA] scan). In those at increased fracture risk, the median 10-year probability of hip and major osteoporotic fracture was 11.2% and 22.8%, vs 4.1% and 11.5% in those deemed not at risk. An osteoporosis diagnosis was recorded in 804 patients (21.2%); most (79.7%) of these were at increased fracture risk. The treatment gap was 74.6%, varying from 53% in Ireland to 91% in Germany. Patients with an osteoporosis diagnosis were found to have a lower treatment gap than those without a diagnosis, with an absolute reduction of 63%. Conclusions There is a large treatment gap in women aged ≥ 70 years at increased risk of fragility fracture in routine primary care across Europe. The gap appears to be related to a low rate of osteoporosis diagnosis

The rise and fall of Anopheles arabiensis (Diptera: Culicidae) in a Tanzanian village

The continual recruitment of new individuals makes it difficult to study both the survival of multivoltine mosquitoes, and the size of the infectious reservoir in narural populations of malaria vectors. During long-term surveillance of a population of Anopheles gambiae Giles sensu lato in a Tanzanian village by daily light trapping, a temporary dry spell resulted in the cessation of recruitment for a period of 33 days, and a decline in numbers of A. arabiensis Patton caught from over 2000 to less than 10 in a sentinel house. Traps placed elsewhere in the village indicated similar proportionate declines although numbers caught varied according to location. A survival rate of 83% per day was estimated from the rate of population decline. Survival was unrelated to the size of the mosquitoes. The infectious reservoir (the chance of a mosquito acquiring an infection) was estimated to be 2% per feed. The exploitation of fortuitous events which temporarily eliminate a single stage in the life cycle has general applicability in the study of the bionomics of multivoltine insect

Chern-Simons Invariants of Torus Links

We compute the vacuum expectation values of torus knot operators in Chern-Simons theory, and we obtain explicit formulae for all classical gauge groups and for arbitrary representations. We reproduce a known formula for the HOMFLY invariants of torus links and we obtain an analogous formula for Kauffman invariants. We also derive a formula for cable knots. We use our results to test a recently proposed conjecture that relates HOMFLY and Kauffman invariants.Comment: 20 pages, 5 figures; v2: minor changes, version submitted to AHP. The final publication is available at http://www.springerlink.com/content/a2614232873l76h6

Numerical algorithm to recover contrast dynamics in 3D digital subtraction angiography data-sets: a preliminary clinical validation

Several neurosurgical procedures, such as ArteroVenous Malformations (AVMs) and StereoElectroEncephaloGraphy (SEEG) require accurate reconstruction of the cerebral vascular tree, as well as the classification of arteries and veins, to increase the safety of the intervention. We propose ART-3.5D, a novel approach to recover the dynamic information from standard Cone Beam Computed Tomography Angiography scans based on the post- processing of both the segmented angiogram and the raw data-set

String theory and the Kauffman polynomial

We propose a new, precise integrality conjecture for the colored Kauffman polynomial of knots and links inspired by large N dualities and the structure of topological string theory on orientifolds. According to this conjecture, the natural knot invariant in an unoriented theory involves both the colored Kauffman polynomial and the colored HOMFLY polynomial for composite representations, i.e. it involves the full HOMFLY skein of the annulus. The conjecture sheds new light on the relationship between the Kauffman and the HOMFLY polynomials, and it implies for example Rudolph's theorem. We provide various non-trivial tests of the conjecture and we sketch the string theory arguments that lead to it.Comment: 36 pages, many figures; references and examples added, typos corrected, final version to appear in CM

Management of bone metastasis and cancer treatment-induced bone loss during the COVID-19 pandemic: An international perspective and recommendations

Optimum management of patients with cancer during the COVID-19 pandemic has proved extremely challenging. Patients, clinicians and hospital authorities have had to balance the risks to patients of attending hospital, many of whom are especially vulnerable, with the risks of delaying or modifying cancer treatment. Those whose care has been significantly impacted include patients suffering from the effects of cancer on bone, where delivering the usual standard of care for bone support has often not been possible and clinicians have been forced to seek alternative options for adequate management. At a virtual meeting of the Cancer and Bone Society in July 2020, an expert group shared experiences and solutions to this challenge, following which a questionnaire was sent internationally to the symposium's participants, to explore the issues faced and solutions offered. 70 respondents, from 9 countries (majority USA, 39%, followed by UK, 19%) included 50 clinicians, spread across a diverse range of specialties (but with a high proportion, 64%, of medical oncologists) and 20 who classified themselves as non-clinical (solely lab-based). Spread of clinician specialty across tumour types was breast (65%), prostate (27%), followed by renal, myeloma and melanoma. Analysis showed that management of metastatic bone disease in all solid tumour types and myeloma, adjuvant bisphosphonate breast cancer therapy and cancer treatment induced bone loss, was substantially impacted. Respondents reported delays to routine CT scans (58%), standard bone scans (48%) and MRI scans (46%), though emergency scans were less affected. Delays in palliative radiotherapy for bone pain were reported by 31% of respondents with treatments often involving only a single dose without fractionation. Delays to, or cancellation of, prophylactic surgery for bone pain were reported by 35% of respondents. Access to treatments with intravenous bisphosphonates and subcutaneous denosumab was a major problem, mitigated by provision of drug administration at home or in a local clinic, reduced frequency of administration or switching to oral bisphosphonates taken at home. The questionnaire also revealed damaging delays or complete stopping of both clinical and laboratory research. In addition to an analysis of the questionnaire, this paper presents a rationale and recommendations for adaptation of the normal guidelines for protection of bone health during the pandemic

Prevalence of FRAX risk factors and the osteoporosis treatment gap among women ≥ 70 years of age in routine primary care across 8 countries in Europe

Summary We studied whether elderly women at risk for fractures receive primary care treatment to prevent fracture. We found that across Europe, women at risk are often not identified, and less than half of such women receive appropriate treatment. Finally, women diagnosed with osteoporosis are much more likely to receive treatment. Purpose To examine the relationship between risk factors for fragility fracture (FF) and osteoporosis (OP) treatment gap in elderly women across Europe, and compare the prevalence of risk factors between countries. Methods Demographic and clinical information was collected from women ≥ 70 years visiting primary care physicians in Belgium, France, Germany, Ireland, Poland, Slovakia, Switzerland, and the UK. Increased risk of FF was defined by the presence of 1 or more criteria (history of fracture, 10-year fracture probability, or T-score ≤  − 2.5). Results There were 3798 women in total. Treatment gap (proportion at increased risk of FF not receiving treatment for OP) varied from 53.1 to 90.8% across countries, and the proportion of patients at increased risk of FF varied from 41.2 to 76.1%. Across countries, less than 50% of patients with increased risk of FF had a diagnosis of OP. Previous fracture was the most common risk factor, with similar prevalence across most countries; other risk factors varied widely. The treatment gap was reduced in patients with an OP diagnosis in all countries, but this reduction varied from 36.5 to 79.4%. The countries with the lowest rates of bone densitometry scans (Poland, France, and Germany; 8.3–12.3%) also had the highest treatment gap (82.2 to 90.8%). Conclusions This study highlights differences across Europe in clinical risk factors for fracture, rates of densitometry scanning, and the rates of OP diagnosis. More emphasis is needed on risk assessment to improve the identification and treatment of elderly women at risk for fracture