Determining the Electrical Losses in the Electrical Supply Line of a Sprinkler Using Autonomous Asynchronous Generator

The use of an asynchronous generator to power the electrical equipment of the sprinkler is a comprehensive solution that allows you to reduce electrical losses in the supply line. The problem of reactive power compensation for sprinkler machines can be solved by dividing capacitor units into main and additional, the main one is to create the required excitation current in the asynchronous generator, and the additional one is to compensate for the reactive component of the electric motor current. Moreover, an additional unit is installed directly at the outputs of the booster pump to unload the line, and the main capacitor unit is installed near the asynchronous generator.

Comparing left atrial indices by CMR in association with left ventricular diastolic dysfunction and adverse clinical outcomes

Left atrial (LA) features are altered when diastolic dysfunction (DD) is present. The relations of LA features to the DD severity and to adverse outcomes remain unclear using CMR images. We sought to compare LA features including volumes, emptying fraction, and strains as predictors of left ventricular (LV) DD and adverse outcomes. We compared four groups including normal controls (n = 32), grade I DD (n = 69), grade II DD (n = 42), and grade III DD (n = 21). DD was graded by echocardiography following the current ASE guidelines. Maximum LA volume (LAVmax), minimum LA volume (LAVmin), and LA emptying fraction (LAEF) were assessed using CMR cine images. Phasic LA strains including reservoir, conduit, and booster pump strain were assessed by feature tracking. The outcome was a composite of hospital admissions for heart failure and all-cause mortality analyzed using Cox proportional hazard models. LAVmax and LAVmin were progressively larger while LAEF and LA strain measures were lower with worsening degree of DD (all p < 0.001). Among 132 patients with DD, 61 reached the composite outcome after on average 36-months of follow-up. Each of the LA parameters except for LA conduit strain was an independent predictor of the outcome in the adjusted Cox proportional hazard models (all p < 0.001). They remained significant outcome predictors after the model additionally adjusted for LV longitudinal strain. The AUC of outcome prediction was highest by LAEF (0.760) followed by LA reservoir strain (0.733) and LAVmin (0.725). Among all the LA features, increased LA volumes, reduced LAEF, reduced LA reservoir and booster pump strains were all associated with DD and DD severity. While LA strains are valuable, conventional parameters such as LAEF and LAVmin remain to be highly effective in outcome prediction with comparable performance.

Re-design the use of PV to distribute water from tanks to rural area for Mentawai especially in Central Siberut sub-district

The redesign of the water pump stuck in the district of Central Siberut is reused by using the Solar Panel as an alternative energy source. The materials and tools used are Booster pump, pipe, air valve, wash out, blow off and gate valve. The booster pump is used to pump high pressure water from the tank so that it can reach Saibi village, where Saibi village is the farthest village compared to Simulaklak village, where the distance from the tank to Simulaklak village is only 1.5 km and the tank to Saibi village is 4.5 km the elevation difference between the tank and the village of Saibi is 25 meters above sea level. The total water demand in Simulaklak and Saibi villages is 17.63 liters / second with flow rates in Simulaklak and Saibi villages of 2.25 m / sec and 1.69 m / sec, for the pump head obtained from the tank to Simulaklak village is 72,1 m and the pump head from the tank to Saibi Village is 120.31 m. The standard atmospheric pressure obtained for Simulaklak village is 10,284 mH2O and for Saibi village is 10.301 mH2O. Booster pump is an alternative that can be used for distributing water from the tank to the village.

Automatic Unloading Liquid Rocket Engine Fuel Feed System Booster Pump Radial Thrust Bearings from Axial Force

Increasing the suction capacity, efficiency and energy parameters of high-speed pumps is an important task in the development of power systems in the aerospace industry, as well as in their application in energy and oil production. With improved cavitation properties, the pumps can operate at a higher shaft speed, and at its given value - with lower cavitation reserves, i.e. at a reduced inlet pressure. When the shaft speed increases, the pump weight and overall dimensions decrease. To increase the anti-cavitation qualities of pumps in the power system, auxiliary (booster) pumping units are used, creating the pressure necessary for the cavitation-free operation of high-pressure and high-speed main pumps of the engine fuel supply system. In accordance with its purpose, the booster pump must provide the required supply pressure of the specified flow rate at the lowest possible liquid pressure at the inlet. At the same time, the efficiency of the booster pump unit should be maximum, and the overall dimensions and weight should be minimal. The last two characteristics predetermine the maximum possible number of revolutions of the pump shaft. Ensuring the operability of the ball-bearing supports of the fuel supply units is one of the most important and complex tasks in the development of modern and promising liquid rocket engines (LRE), especially reusable ones. This task has always been one of the priorities in the fine-tuning the fuel feed units of such engines. The article proposes a method for calculating and controlling the unloading liquid rocket engine booster pump radial thrust bearings from axial force. The method can be applied in the entire range of liquid rocket engine calculations. The further development of this work will be mathematical modeling of the operation of the booster pump automatic axial force unloading.

Comprehensive assessment of left atrial and ventricular remodeling in paroxysmal atrial fibrillation by the cardiovascular magnetic resonance myocardial extracellular volume fraction and feature tracking strain

Atrial fibrillation (AF) is a progressive disease that starts with structural or functional changes in the left atrium and left ventricle, and evolves from paroxysmal toward sustained forms. Early detection of structural or functional changes in the left atrium and left ventricle in the paroxysmal stage could be useful for identifying a higher risk of progression to persistent AF and future cardio-cerebrovascular events. The aim of this study was to test the hypothesis that the feature tracking (FT) left atrial (LA) strain and left ventricular (LV) extracellular volume fraction (ECV) derived from cardiovascular magnetic resonance (CMR) could detect early changes in remodeling of the left atrium and ventricle in the paroxysmal AF (PAF) stage. The participants were comprised of 106 PAF patients (age, 66.1 ± 10.7 years; 66% male) who underwent clinical CMR before pulmonary vein isolation and 20 control subjects (age, 68.3 ± 8.6 years; 55% male). The CMR-FT LA strain/phasic function and LV-ECV were compared between the PAF and control groups. The total and passive LA empty fraction (LAEF) and LA strain (corresponding to LA reservoir and conduit function) were decreased in the PAF group as compared to the control group. However, active LAEF (corresponding to the LA booster pump function) did not differ significantly between the PAF group (33.9 ± 10.9%) and control group (37.9 ± 13.3%, p = 0.15), while the active LA strain (corresponding to the LA booster pump function) was significantly decreased in the PAF group (11.4 ± 4.3 vs. 15.2 ± 5.6%, p = 0.002). The LV-ECV was significantly greater in the PAF group (28.7 ± 2.8%) than control group (26.6 ± 2.0%, p = 0.002). In the PAF group, the LV-ECV correlated significantly with the E/e′ and LA volume index. Regarding the LA strain, correlations were seen between the LV-ECV and both the reservoir function and conduit function. CMR-FT LA strain in combination with the LV-ECV in a single clinical study offers a potential imaging marker that identifies LA/LV remodeling including subtle LA booster pump dysfunction undetectable by the conventional booster pump LAEF in the PAF stage.

The Role of Left-Atrial Mechanics Assessed by Two-Dimensional Speckle-Tracking Echocardiography to Differentiate Hypertrophic Cardiomyopathy from Hypertensive Left-Ventricular Hypertrophy

Hypertrophic cardiomyopathy (HCM) and arterial hypertension (HTN) are conditions with different pathophysiology, but both can result in left-ventricular hypertrophy (LVH). The role of left-atrial (LA) functional changes detected by two-dimensional speckle-tracking echocardiography (STE) in indicating LVH etiology is unknown. Methods: We aimed to characterize LA mechanics using STE in LVH patients with HCM and HTN. LA 2D volumetric and STE parameters were analyzed in 86 LVH patients (43 HCM and 43 isolated HTN subjects) and 33 age- and sex-matched controls. Results: The volumetric study showed that LA reservoir and conduit function were impaired in the HCM group compared to controls, while, in the HTN group, only LA conduit function was deteriorated. The HCM group had all three STE-derived LA functions impaired compared to controls. The HTN group, consistently with volumetric analysis, had solely LA conduit function reduced compared to controls. Ratios of LA booster-pump strain (S) and strain rate (SR) to interventricular septum (IVS) thickness were the most accurate parameters to discriminate between HCM and HTN. The subgroup harboring sarcomeric pathogenic (P)/likely pathogenic (LP) variants had reduced LA booster-pump S and SR compared with the genotype-negative subgroup. Conclusions: LA reservoir, conduit, and pump functions are decreased in HCM compared to HTN patients with similar LVH. We report the ratios between LA contraction S/SR and IVS thickness as novel parameters with high accuracy in discriminating LVH due to HCM. The presence of P/LP variants in sarcomeric or sarcomeric-associated genes could be associated with more severe LA dysfunction.

Comprehensive Assessment of Left Atrial and Ventricular Remodeling in Paroxysmal Atrial Fibrillation by Cardiovascular Magnetic Resonance Myocardial Extracellular Volume Fraction and Feature Tracking Strain

Atrial fibrillation (AF) is a progressive disease that starts with structural or functional changes in the left atrium and left ventricle, and evolves from paroxysmal toward sustained forms. Early detection of structural or functional changes in the left atrium and left ventricle in the paroxysmal stage could be useful for identifying higher risk of progression to persistent AF and future cardio-cerebrovascular events. The aim of this study was to test the hypothesis that feature tracking (FT) left atrial (LA) strain and left ventricular (LV) extracellular volume fraction (ECV) derived from cardiovascular magnetic resonance (CMR) could detect the early changes of remodeling in the left atrium and ventricle in the stage of paroxysmal AF (PAF).Participants comprised 106 PAF patients (age, 66.1 ± 10.7 years; 66% male) who underwent clinical CMR before pulmonary vein isolation and 20 control subjects (age, 68.3 ± 8.6 years; 55% male). CMR-FT LA strain/phasic function and LV-ECV were compared between the PAF and control groups. Total and passive LA empty fraction (LAEF) and LA strain (corresponding to LA reservoir and conduit function) were decreased in the PAF group compared to the control group. However, active LAEF (corresponding to LA booster pump function) did not differ significantly between the PAF group (33.9 ± 10.9%) and control group (37.9 ± 13.3%, p = 0.15), while active LA strain (corresponding to LA booster pump function) was significantly decreased in the PAF group (11.4 ± 4.3 vs. 15.2 ± 5.6%, p = 0.002). LV-ECV was significantly greater in the PAF group (28.7 ± 2.8%) than in the control group (26.6 ± 2.0%, p = 0.002). In the PAF group, LV-ECV correlated significantly with E/e’ and LA volume index. Regarding LA strain, correlations were seen between LV-ECV and both reservoir function and conduit function.CMR-FT LA strain in combination with LV-ECV offers a potential imaging marker that identifies LA/LV remodeling including subtle LA booster pump dysfunction undetectable by conventional booster pump LAEF in the stage of PAF. These findings provide new insights into LA-LV interactions and further investigation regarding association between perpetuation of AF and LA functional remodeling in PAF patients.

Assessment of Left Atrial Function in Essential Hypertension Patients With Normal Left Ventricle Function by Volume-derived Values and Two-dimensional Strain

Background: To investigate left atrial(LA) function in essential hypertension(EHT) patients by using volume-derived values, two-dimensional strain. Methods: 51 normal subjects and 95 EHT patients(without LVH: 50, and with LVH: 45) were enrolled for this research. LA Volume-derived index was measured in apical 4-, 2-chamber views by Simpson′s method. LA strain(S-reservoir, S-conduit, S-booster pump) and strain rate (SR-reservoir, SR-conduit, SR-booster pump), representing the reservoir, conduit and booster pump functions, respectively, were measured by two-dimensional speckle tracking echocardiography(STE).Results: Volume-derived values(contain Total LAEF, passive LAEF and active LAEF) and strain-derived values(S-reservoir, S-conduit, Sr-reservoir, Sr-conduit and Sr-booster pump) in EHT patients were significantly lower than normal subjects. Correlation test showed LA stiffness had a strong correlation with LA conduit function in EHT patients. The AUC values were higher for detection LA conduit function than LA reservoir and booster pump function in EHT patients. LA expansion index and LA stiffness also have the higher AUC with higher sensitivity and specificity values for detection the LA dysfunctions in EHT patients. Conclusions: In this study, we concluded that LA functions were damaged in EHT patients, which could be detect by LA volume-derived values and two-dimensional strain sensitively and reproductively. LA stiffness maybe a predictor for LV remodelling in EHT patients.

Correlations between left atrial volumes and strains in healthy adults - a three-dimensional speckle-tracking echocardiographic study

Funding Acknowledgements Type of funding sources: None. Introduction. Left atrium (LA) is a dynamic structure, which can be characterized by several volumetric and functional properties. Not only volumetric changes could be detected during cardiac cycle, but contractility of its walls have also special quantitative properties. Three-dimensional (3D) speckle-tracking echocardiography (3DSTE) is a new imaging technique with capability of featuring changes in both LA volume and function by several parameters based on a virtual 3D LA model respecting cardiac cycle at the same time. This ability of 3DSTE makes an opportunity to examine correlations between LA volumes and contractility features. Due to the limited number of studies assessing these physiologic relationships, the present study aimed to test correlations between LA volumes, volume-based functional properties and strains respecting cardiac cycle in healthy adults by 3DSTE. Methods. The present study comprised 217 healthy adult volunteers (mean age: 33.4 ± 12.7 years, 112 males) without any symptoms, known diseases or other states, which could affect results. None of them received any medication at the time of examination. Complete two-dimensional (2D) Doppler echocardiography and 3DSTE have been performed in all cases. Results. LA stroke volumes increased with maximum LA volume (Vmax) in reservoir, conduit and booster pump phases of LA function. LA emptying fraction (EF) remained unchanged in LA reservoir phase (total atrial EF, TAEF) with the increase in Vmax (TAEF at Vmax &lt; 30 ml = 51.9 ± 13.7% vs. TAEF at Vmax &gt; 50 ml = 50.9 ± 10.9%, p = ns). Significant reduction in LA-EF could be detected in LA conduit phase (passive atrial EF, PAEF), if Vmax proved to be larger than 50 ml (PAEF at Vmax &lt; 30 ml = 34.0 ± 13.2% vs. PAEF at Vmax &gt; 50 ml = 27.5 ± 12.6%, p &lt; 0.05). In booster pump function LA-EF (active atrial EF, AAEF) did not show significant alterations with the increase of Vmax (AAEF at Vmax &lt; 30 ml = 26.9 ± 14.7% vs. PAEF at Vmax &gt; 50 ml = 31.7 ± 11.7%, p = ns). Global peak LA radial strain (RS) (at Vmax &lt; 30 ml = -11.7 ± 8.9% vs. at 30 ml ≤ Vmax ≤ 50 ml = -15.4 ± 7.7% and at Vmax &gt; 50 ml = -14.7 ± 6.8%, p &lt;0.05 and p &lt; 0.05, respectively) and 3D strain (3DS) (at Vmax &lt; 30 ml = -5.5 ± 5.7% vs. at 30 ml ≤ Vmax ≤ 50 ml = -7.5 ± 5.6% and at Vmax &gt; 50 ml = -8.0 ± 5.0%, p &lt; 0.05 and p &lt; 0.05, respectively) increased with Vmax only until a point. LA-RS and LA-3DS at atrial contraction similarly increased with Vmax. The other strain parameters did not show any changes. Conclusions. LA-RS and LA-3DS, objective features of LA contractility do not increase beyond a point in parallel with an increase in maximum LA volume in healthy subjects.