Identification of heat exchangers according to the criterion of energy efficiency

The article presents the results of the analysis of the characteristics of heat exchangers methods for determining their mathematical models. The necessity of the availability of the mathematical model during the synthesis of automatic control systems with desired properties. The method of identification of the thermal control object by the testing control action is proposed. Since technological control objects always be an energy of interaction the energy efficiency criterion applied for automatic formation of the control action. Also the analytical self-adjusting system with a reference model in the form of an integrating link was applied. From the analytical researches it follows that the movement of the system along the optimal trajectory occurs at a constant speed and does not depend on the properties of the control object, and the optimal control depends on the properties of the control object, time, and technological requirements. It is shown that mathematical models of heat exchangers of the first and second orders are determined quite simply. The accuracy of the mathematical model parameters is limited only by the accuracy of the experimental data. The quality of control systems with desired properties, synthesized by experimental, and accurate models are virtually indistinguishable

Risks and reliability assessment of construction processes

Improving the reliability of the implementation of construction schedules for a complex of structures (where the level of quality, timing, and costs is taken into account) can be achieved by creating reserves: time and resources. The reserve of time, the main types of technical, labor, and material resources due to the creation of special structures is in most cases ineffective due to increased costs. Finding the most effective options for creating the corresponding structures from the standpoint of reliability and efficiency is a rather difficult task. An example is given when planning the construction of buildings of a multifunctional complex, a computational matrix is obtained for the flow organization of works. The assessment of the reliability of compliance with the directive deadline for the erection of the mainframe structures are: the critical chain method, the continuous use of resources method, the method of continuous work of front development

Assessment of the Budesonid Protective Effects in Patients with Cardio-Respiratory Comorbidity During Coronary Bypassing with Artificial Circulation

The objective: evaluation of the effect of budesonide and low-volume mechanical ventilation (LVMV) on pulmonary volemia, oxygen transport and respiratory biomechanics in patients with concurrent ischemic heart disease (IHD) and chronic obstructive pulmonary disease (COPD) during coronary artery bypass grafting (CABG) with artificial circulation (AC).Subjects and Methods. 50 patients with concurrent IHD and COPD were enrolled in the study. During AC, patients of Group I (20 people) received mechanical ventilation with the peak inspiratory pressure of 15 mbar, tidal volume of 3‒4 ml/kg, positive end-expiratory pressure of 5 mbar in combination with inhalation of nebulized budesonide. In Group II (30 people), the similar isolated respiratory support was provided. Pulmonary blood volume, indices of extravascular lung water (EVLW), pulmonary vascular permeability (PVPI), oxygen delivery (DO2I) and consumption (VO2I), oxygen extraction ratio (O2ER), pulmonary shunt fraction (Qs/Qt), oxygenation index were determined. The study consisted of 3 stages: before AC, after its completion and one day after CABG.Results. Before CABG, the EVLW index in all patients exceeded the standard level by 67‒72%. After weaning from AC, it decreased by 23% in Group I and by 8% in Group II. In patients receiving budesonide, PVPI significantly decreased after artificial circulation, while in patients from Group II, it remained unchanged. DO2I and O2ER in all patients were within the reference range, and VO2I was below it with a minimum value in Group II after weaning from AC. In this cohort, the Qs/Qt level was significantly higher, while OI was lower versus patients from Group I. Among patients who received budesonide immediately after AC and 2 hours after it, pulmonary resistance decreased while lung compliance increased. In Group II, those parameters changed oppositely. In Group I, one case of hydrothorax was recorded, and in Group II, 2 patients were diagnosed with polysegmental pneumonia and 2 patients – with pneumothorax. The median duration of mechanical ventilation in the postoperative period made 220 minutes in Group I, and 290 minutes in Group II (p = 0.018).Conclusion. In patients with concurrent IHD and COPD, use of the combination of low-volume mechanical ventilation and inhalation of nebulized budesonide during AC stabilizes the volemic status of the lungs, improves the oxygenating function and respiratory biomechanics in the postperfusion and early postoperative periods of CABG

Оценка протективных эффектов будесонида у больных с кардиореспираторной коморбидностью при коронарном шунтировании с искусственным кровообращением

The objective: evaluation of the effect of budesonide and low-volume mechanical ventilation (LVMV) on pulmonary volemia, oxygen transport and respiratory biomechanics in patients with concurrent ischemic heart disease (IHD) and chronic obstructive pulmonary disease (COPD) during coronary artery bypass grafting (CABG) with artificial circulation (AC).Subjects and Methods. 50 patients with concurrent IHD and COPD were enrolled in the study. During AC, patients of Group I (20 people) received mechanical ventilation with the peak inspiratory pressure of 15 mbar, tidal volume of 3‒4 ml/kg, positive end-expiratory pressure of 5 mbar in combination with inhalation of nebulized budesonide. In Group II (30 people), the similar isolated respiratory support was provided. Pulmonary blood volume, indices of extravascular lung water (EVLW), pulmonary vascular permeability (PVPI), oxygen delivery (DO2I) and consumption (VO2I), oxygen extraction ratio (O2ER), pulmonary shunt fraction (Qs/Qt), oxygenation index were determined. The study consisted of 3 stages: before AC, after its completion and one day after CABG.Results. Before CABG, the EVLW index in all patients exceeded the standard level by 67‒72%. After weaning from AC, it decreased by 23% in Group I and by 8% in Group II. In patients receiving budesonide, PVPI significantly decreased after artificial circulation, while in patients from Group II, it remained unchanged. DO2I and O2ER in all patients were within the reference range, and VO2I was below it with a minimum value in Group II after weaning from AC. In this cohort, the Qs/Qt level was significantly higher, while OI was lower versus patients from Group I. Among patients who received budesonide immediately after AC and 2 hours after it, pulmonary resistance decreased while lung compliance increased. In Group II, those parameters changed oppositely. In Group I, one case of hydrothorax was recorded, and in Group II, 2 patients were diagnosed with polysegmental pneumonia and 2 patients – with pneumothorax. The median duration of mechanical ventilation in the postoperative period made 220 minutes in Group I, and 290 minutes in Group II (p = 0.018).Conclusion. In patients with concurrent IHD and COPD, use of the combination of low-volume mechanical ventilation and inhalation of nebulized budesonide during AC stabilizes the volemic status of the lungs, improves the oxygenating function and respiratory biomechanics in the postperfusion and early postoperative periods of CABG.Цель: оценка влияния будесонида и малообъемной искусственной вентиляции легких (ИВЛ) на показатели легочной волемии, транспорта кислорода и биомеханики дыхания у больных с ишемической болезнью сердца (ИБС) с сопутствующей хронической обструктивной болезнью легких (ХОБЛ) при коронарном шунтировании (КШ) с искусственным кровообращением (ИК).Материалы и методы. В исследование включено 50 больных ИБС и ХОБЛ. Больным 1-й группы (20 человек) во время ИК продолжали ИВЛ с пиковым давлением на вдохе 15 мбар, дыхательным объемом 3–4 мл/кг, положительным давлением в конце выдоха 5 мбар в сочетании с ингаляцией небулизированного будесонида. Во 2-й группе (30 человек) проводили изолированную респираторную поддержку в аналогичном режиме. Определяли легочный объем крови, индексы внесосудистой воды легких (ИВСВЛ), проницаемости легочных сосудов (ИПЛС), доставки (DO2I) и потребления (VO2I) кислорода, коэффициент его утилизации (O2ER), фракцию легочного шунтирования крови (Qs/Qt), индекс оксигенации (ИО), биомеханические параметры легких. Исследование проводили на трех этапах: до начала ИК, после его завершения и через сутки после КШ.Результаты. До КШ показатель ИВСВЛ у всех больных превышал нормативный уровень на 67–72%. После отхода от ИК в 1-й группе он снижался на 23%, а во 2-й – на 8%. У больных, получавших будесонид, ИПЛС после ИК статистически значимо снижался, а у лиц 2-й группы он оставался неизменным. DO2I и O2ER у всех пациентов находились в референсном диапазоне, а VO2I был ниже его с минимальным значением во 2-й группе после отхода от ИК. В этой когорте уровень Qs/Qt был статистически значимо выше, а ИО – ниже, чем у больных 1-й группы. Среди лиц, получавших будесонид, сразу после ИК и через 2 ч после него сопротивление легочной ткани снижалось на фоне повышения ее комплаенса. Во 2-й группе имела место противоположная динамика этих показателей. В 1-й группе зафиксирован один случай гидроторакса, во 2-й – у 2 больных диагностирована полисегментарная пневмония и у 2 – пневмоторакс. Медиана продолжительности ИВЛ в послеоперационном периоде в 1-й группе составила 220 мин, во 2-й – 290 мин (p = 0,018).Вывод. У больных с ИБС и ХОБЛ применение комбинации малообъемной ИВЛ и ингаляции небулизированного будесонида в период ИК стабилизирует волемический статус легких, улучшает их оксигенирующую функцию и биомеханику дыхания в постперфузионном и раннем послеоперационном периодах КШ

Foreign Policy of India as the Reflection of Change in its Ruling Elite

The article examines the changes in the formulation, prioritisation and implementation of India’s foreign policy objectives as a result of a significant renewal of its political elite, triggered by the economic reforms that began in the 1990s. It is argued that India’s ruling elite is now largely identical to its political elite, whose mindset, although considerably younger and better educated, is more than ever defined by its self-identification with traditional values, which are religious and, for the vast Hindu majority, caste-based. At the same time, the composition of India’s elite has broadened during the reform years, mainly through the inclusion of middle and even lower castes in the traditional hierarchy. Many of its representatives tend to associate the strengthening of the country with a return to the “correct” cultural and civilisational basis which, in the centuries before foreign conquest, gave India what the y saw as its natural primacy in the world. The main change is the emergence of a sense of self-confidence among the elite, on which the so-called “new nationalism” of the “man of the people”, the current Prime Minister N. Modi, is based. Drawing on his statements, speeches by Foreign Secretary S. Jaishankar, and articles by Indian and Russian scholars, the author shows the innovations introduced by the Prime Minister in promoting India’s core national interests in a changing world. The article examines the creation of India’s own sphere of influence within the framework of the new Indo-Pacific strategy, the combination of cooperation and competition in relations with China, the reasons for the dynamic expansion of interaction with the United States and the “red lines” involved, the motives for developing a particularly privileged strategic partnership with Russia and for using multilateral formats, and the return to India’s agenda of the task of gaining the status of the main voice of the Global South. It is concluded that approaches to the imperative of building a multipolar world order “in which India would be a strong pole”, based on the priority goal of establishing for it the status of a great power and a global actor in world politics, create historic opportunities for increasing Russian-Indian interaction

Improving the Stability of Optimal Control Systems for Thermal Processing

The article presents the results of the analysis different methods to enhance theaccuracy, sustainability and energy efficiency of automatic control systems. Shows the constraints on the possibility of increasing the accuracy and stability of automatic control systems. The necessity of the use of self-tuning systems for control of nonstationary objects, which include the installation of thermal processing of building materials and products. Theblock diagram of the analytical self-tuning system optimal reference model.</jats:p