Multiple Mechanical Ventilation: historical review and cost analysis

In times of crisis in public health where the resources available in the hospital network are scarce and these must be used to the fullest, innovative ideas arise, which allow multiplying the use of existing resources, as artificial mechanical ventilators can be. These can be used in more than one patient, by attaching a device to distribute the mixture of air and oxygen from the ventilator being used simultaneously (multiple mechanical ventilation). This idea, although innovative, has generated controversy among the medical community, as many fear for the safety of their patients, because attaching such devices to the ventilator loses control over the mechanical ventilation variables of each patient and can only maintain general vigilance over the ventilator. These misgivings about the device have led several researchers to take on the task of verifying the reliability of this flow splitter connector. It is for this reason that this article presents a thorough review of the studies carried out on the subject and additionally shows an analysis of comparative costs between the acquisition of a mechanical ventilator and the flow division system.

Characteristics of Tidal Discharge and Phase Difference at a Tidal Channel Junction Investigated Using the Fluvial Acoustic Tomography System

This study investigates the tidal discharge division and phase difference at branches connected to a channel junction. The tidal discharge at three branches (eastern, western, and northern branches) was continuously collected using the fluvial acoustic tomography system (FATS). The discharge asymmetry index was used to quantify the flow division between two seaward branches (eastern and western branches). The cross-wavelet method was applied to calculate the phase difference between the tidal discharge and water level. The discharge asymmetry index shows that the inequality of flow division is obviously prominent during the spring tide duration, where the eastern branch has the capability to deliver greater amounts of subtidal discharge, approximately 55–63%, compared with the western branch. However, the equality of flow division between the eastern and western channels can be observed clearly during the neap tide period. The wavelet analysis shows that the phase difference at the western branch is higher than at the eastern branch, because the geometry of the western branch is more convergent than that of the eastern branch. Accordingly, the amplitude of the tidal wave at the western branch is more magnified compared with that at the eastern branch. Moreover, the phase difference at the northern branch is greater than at the two seaward branches, implying that the phase difference is slightly increased after passing through the junction into the northern branch.

Studies of rational methods of water selection in water intake areas of hydroelectric power plants

Up to 2021, 42 new hydropower stations will be created in Uzbekistan and 32 existing hydropower stations will be repaired. Hydraulic engineering designers face a number of problems with the open flow division nodes in the field, which are part of the hydraulic structures of such hydropower plants. Considering the above, the main objectives of the research were determined: a) development of a refined method for the hydraulic calculation of flow division nodes with a quiet flow regime; b) the development of methods for predicting deformation of the channel in the area of the division node. The studies were carried out using theoretical and experimental studies using the equation for changing the amount of movement, laboratory studies on a hydraulic model, field surveys of existing water intake nodes, as well as analysis of experimental data available in the literature on this issue. Based on the theoretical and experimental studies, recommendations were made for the open flow division nodes. These recommendations are valid for division nodes at a division angle not exceeding 90°, for prismatic channels of rectangular cross section with relatively small bottom slopes. These recommendations are intended for flows with values of B / H = 3 ÷7.