ИДЕНТИФИКАЦИЯ ПРИЖИМНЫХ УСИЛИЙ КРЕПЛЕНИЙ КОНСТРУКЦИИ С ИСПОЛЬЗОВАНИЕМ НЕЙРОННЫХ СЕТЕЙ НА ОСНОВЕ КОНЕЧНО-ЭЛЕМЕНТНОЙ МОДЕЛИ ДЛЯ КОМПРЕССОРНО-КОНДЕНСАТОРНОЙ УСТАНОВКИ

The article provides a brief review of a condensing unit and problems of mathematic simulation. It examines the influence of pretension on the strain-stress state of a construction by means of finiteelement modeling. The arrangement of a set of input-output data for neural network is also considered. The article investigates a possibility to predict mounting precision via neural networks; by analogy with the above calculations it examines the option to detect clamping forces on mounting compressorcondensing unit. Дается краткий обзор компрессорно-конденсаторной установки и задач математического моделирования. Проводится анализ влияния усилий предварительной затяжки на напряженно-деформированное состояние модели фланца с использованием системы конечно-элементного моделирования, подготовка входных и выходных данных для обучения нейронной сети. Проверяется возможность прогнозирования погрешностей крепления элементов конструкции фланца с использованием нейронных сетей. По аналогии с проведенными расчетами исследуется возможность идентификации прижимных усилий креплений в конструкции компрессорно-конденсаторного агрегата

ВЛИЯНИЕ УПРОЩАЮЩИХ ПРЕДПОЛОЖЕНИЙ В КОНЕЧНОЭЛЕМЕНТНЫХ МОДЕЛЯХ КОМПРЕССОРНО-КОНДЕНСАТОРНЫХ АГРЕГАТОВ НА СПЕКТР СОБСТВЕННЫХ ЧАСТОТ

The article touches upon such issues as mathematical model validity and accuracy of the obtained results, considering features of the finite element approach to condensing unit parametric modeling. Acceptable simplifying assumptions of a finite-element model of a condensing unit to define natural frequency spectrum is investigated and modal analyses of several simplified models are conducted. Eigensolution is implemented on a specific example of a system. В статье затрагиваются проблемы адекватности математической модели и точности получаемых результатов, учитывая особенности конечно-элементного подхода при проектировании параметрической модели компрессорно-конденсаторных агрегатов. Исследуется допустимая степень упрощения конечно-элементной модели компрессорно-конденсаторного агрегата при определении спектра собственных частот колебаний и проводится модальный анализ конструкции в нескольких упрощенных постановках. Решение задачи о собственных значениях в общем виде реализовано на конкретном примере системы

Ovarian reserve in reproductive age women with type 1 diabetes

Background: Premature aging are frequently observed among individuals with type 1 diabetes. Decrease of ovarian reserve may be one of the characteristics of such process. Aims: To evaluate the ovarian reserve function in female patients of reproductive age with type 1 diabetes in comparison with healthy women. Materials and methods: This study evaluated 224 Caucasian women, age 18–37 years with type 1 diabetes and 230 healthy women of comparable age. Serum concentrations of anti-Mullerian hormone (AMH), inhibin B, follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol, progesterone and testosterone were compared on the 2–3 day of menstrual cycle as ovarian volume and antral follicle count (AFC). In addition, glycated hemoglobin level (HbA1c%) was evaluated. Results: We reveal statistically significant difference in following parameters in diabetic women in comparison with healthy women: AMH, AFC. But even in diabetic patients parameters remained within reference ranges. There was a pronounced negative relationship between the levels of HbA1c% and AMG. Conclusions: Ovarian reserve function parameters decrease in young women with type 1 diabetes in comparison with healthy women, but ovarian reserve parameters are in normal reference range. These findings are important in pregnancy planning consulting by gynecologists and endocrinologists. We must recommend to women with type 1 diabetes more early planning of natural pregnancy for treatment with reproductive technology in cases of prolog absence of nature pregnancy

ОБЗОР ВОЗМОЖНОСТЕЙ ОПТИМИЗАЦИОННЫХ АЛГОРИТМОВ ПРИ МОДЕЛИРОВАНИИ КОНСТРУКЦИЙ КОМПРЕССОРНО-КОНДЕНСАТОРНЫХ АГРЕГАТОВ МЕТОДОМ КОНЕЧНЫХ ЭЛЕМЕНТОВ

A multiobjective optimization problem of a condensing unit frame is considered. Abstract of multiobjective optimization methods and algorithms is given. The article provides an example of genetic algorithm usage for seeking optimal parameters of the unit frame. Рассматривается задача многокритериальной оптимизации рамы компрессорно-конденсаторного агрегата. Дается краткий обзор методов и алгоритмов многокритериальной оптимизации. Приводится пример использования генетического алгоритма для поиска рациональных параметров рамы агрегата.

Ovarian reserve and autoimmune thyroid diseases

Present literature review provides information about clinical trials that evaluated the association of the carriage of antithyroid antibodies (ATA) and the reduction of the ovarian reserve, as well as the effectiveness of assisted reproductive technologies. The ambiguity and sometimes the opposite of the conclusions of different authors, makes it possible to recommend a balanced attitude to the advisability of screening for ATA in women with a reproductive dysfunction as well as the therapeutic measures proposed in some guidelines based on the results of such examination

Copper Coordination Compounds as Biologically Active Agents

Copper-containing coordination compounds attract wide attention due to the redox activity and biogenicity of copper ions, providing multiple pathways of biological activity. The pharmacological properties of metal complexes can be fine-tuned by varying the nature of the ligand and donor atoms. Copper-containing coordination compounds are effective antitumor agents, constituting a less expensive and safer alternative to classical platinum-containing chemotherapy, and are also effective as antimicrobial, antituberculosis, antimalarial, antifugal, and anti-inflammatory drugs. 64Cu-labeled coordination compounds are promising PET imaging agents for diagnosing malignant pathologies, including head and neck cancer, as well as the hallmark of Alzheimer’s disease amyloid-β (Aβ). In this review article, we summarize different strategies for possible use of coordination compounds in the treatment and diagnosis of various diseases, and also various studies of the mechanisms of antitumor and antimicrobial action

Metals in Imaging of Alzheimer’s Disease

One of the hallmarks of Alzheimer’s disease (AD) is the deposition of amyloid plaques in the brain parenchyma, which occurs 7–15 years before the onset of cognitive symptoms of the pathology. Timely diagnostics of amyloid formations allows identifying AD at an early stage and initiating inhibitor therapy, delaying the progression of the disease. However, clinically used radiopharmaceuticals based on 11C and 18F are synchrotron-dependent and short-lived. The design of new metal-containing radiopharmaceuticals for AD visualization is of interest. The development of coordination compounds capable of effectively crossing the blood-brain barrier (BBB) requires careful selection of a ligand moiety, a metal chelating scaffold, and a metal cation, defining the method of supposed Aβ visualization. In this review, we have summarized metal-containing drugs for positron emission tomography (PET), magnetic resonance imaging (MRI), and single-photon emission computed tomography (SPECT) imaging of Alzheimer’s disease. The obtained data allow assessing the structure-ability to cross the BBB ratio

Role of Nonapeptidergic Hypothalamohypophysial Neurosecretory System in Regulation of Thyroid Gland

Available from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

DETECTION OF CLAMPING FORCES ON MOUNTING A CONSTRUCTION VIA NEURAL NETWORK FOR THE FINITE-ELEMENT MODEL OF COMPRESSOR-CONDENSING UNIT

The article provides a brief review of a condensing unit and problems of mathematic simulation. It examines the influence of pretension on the strain-stress state of a construction by means of finiteelement modeling. The arrangement of a set of input-output data for neural network is also considered. The article investigates a possibility to predict mounting precision via neural networks; by analogy with the above calculations it examines the option to detect clamping forces on mounting compressorcondensing unit

SIMPLIFYING ASSUMPTIONS OF CONDENSING UNIT FMITE-ELEMENT MODEL AND THEIR INFLUENCE ON NATURAL FREQUENCY SPECTRUM

The article touches upon such issues as mathematical model validity and accuracy of the obtained results, considering features of the finite element approach to condensing unit parametric modeling. Acceptable simplifying assumptions of a finite-element model of a condensing unit to define natural frequency spectrum is investigated and modal analyses of several simplified models are conducted. Eigensolution is implemented on a specific example of a system