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2021 ◽  
Vol 26 (3) ◽  
Author(s):  
Mykhailo Kostiantynovych Yaremenko ◽  
Kater Klen ◽  
Valerii Yakovych Zhuikov

In the energy balancing system of distributed generation systems with RES (renewable energy sources), in particular with wind turbines, the effective use of the battery of the balancing system depends on the charge-discharge modes that are implemented. To be effectively used in an energy balancing system, the RES control system should coordinate the processes of energy generation and accumulation in the system through the implementation of operational management with forecasting. Depending on the characteristics of the battery and the accuracy of the measurement or prediction of the energy the battery capacity (or the number of batteries) that will provide the specified control range (controlled operation area) needs to be chosen. Empirical relations (equations) devoted to the dependence of the battery capacity on the discharge current and to the change of voltage at the terminals of the battery during direct current discharge were listed. Among the equations Peukert’s law was chosen. A general view of the dependence of the battery capacity on the discharge current was shown. The formula for Peukert's constant (coefficient) was given. 5 Packert's law limitations were listed including the fact that the effect of temperature on the battery is not taken into account. The influence of depth charge-discharge and the number of discharge cycles on the capacitance was shown. In the process of using the battery and increasing the number of charge-discharge cycles, the capacity decreases. Peukert’s formula was extended to be influenced by temperature: both the Peukert’s capacity and the Peukert’s coefficient depend on the temperature because the Peukert’s coefficient depends on the capacity. For further calculations, a rechargeable battery HZB12-180FA from manufacturer HAZE Battery Campany Ltd was chosen. The temperature was taken into account by empirical dependences from the manufacturer and then they were approximated by 3rd order polynomials. Graphical results of the approximation were shown. The formula of dependency between the power of the wind turbine and the wind speed was shown. The connection between wind speed prediction error, amount of power that could not be obtained because of that and the number of batteries that would provide the specified control range (controlled operation area) was shown. Thus, for calculation of the number of batteries the depth of discharge, temperature and prediction (measurement) error were taken into account. Example dependences of the number of batteries on the wind speed error at temperatures of -20 °C, 0 °C and 20 °C were shown. Curves of dependence of the number of batteries of the balancing system on the ambient temperature and the error of wind speed forecasting was constructed. As an example, when the prediction error increases from 10% to 15%, the number of batteries needs to be increased by 1.17 times, and when the temperature decreases from 20 °C to 0 °C, the number of batteries needs to be increased by 1.48 times. The results of the work can be used at the stage of planning the wind turbine when choosing the number and capacity of the batteries to be installed. Possible areas of further research are using Peukert's formulas, generalized for other or different types of batteries, using other formulas, except for Peukert’s one, for taking into account the dependence of battery capacity on discharge current, using a non-empirical approach to include dependency on temperature.


BMJ Open ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. e049737
Author(s):  
Cecilia Jimeno ◽  
Rosa Allyn Sy ◽  
Pepito De La Pena ◽  
Chritopher Cipriano ◽  
Rima Tan ◽  
...  

ObjectiveTo estimate the annual direct medical cost of type 2 diabetes mellitus (T2DM) in hospitals and outpatient care clinics from a healthcare payer perspective in the Philippines.Design and participants(1) A review of electronic hospital records of people with T2DM in two tertiary hospitals—Ospital ng Makati (OsMak) and National Kidney and Transplant Institute (NKTI) and (2) a cross-sectional survey with 50 physicians providing outpatient care for people with T2DM.SettingPrimary, secondary and tertiary healthcare facilities in Metro Manila.Outcome measuresCost of managing T2DM and its related complications in US dollars (USD) in 2016.ResultsA total of 1023 and 1378 people were identified in OsMak and NKTI, with a complication rate of 66% and 74%, respectively. In both institutions, the average annual cost per person was higher if individuals were diagnosed with any complication (NKTI: US$3226 vs US$2242 and OsMak: US$621 vs US$127). Poor diabetes control was estimated to incur higher per person cost than good control in both public outpatient care (poor control, range: US$727 to US$2463 vs good control, range: US$614 to US$1520) and private outpatient care (poor control, range: US$848 to US$2507 vs good control, range: US$807 to US$1603).ConclusionThe results highlight the high direct medical cost resulting from poor diabetes control and the opportunity for cost reduction by improving control and preventing its complications.


2021 ◽  
Vol 5 (5) ◽  
pp. 775-801
Author(s):  
Yuri Appolonievich Sazonov ◽  
Mikhail Albertovich Mokhov ◽  
Inna Vladimirovna Gryaznova ◽  
Victoria Vasilievna Voronova ◽  
Khoren Arturovich Tumanyan ◽  
...  

This article presents the research results that aim to develop promising mesh turbomachines equipped with jet control systems. The turbomachines operating in difficult conditions in oil and gas production are mainly considered. At the same time, some research results can be used in other production branches, including power engineering and transport. Three-dimensional models for computer simulation of net turbines and jet control systems were developed. Prototypes and micromodels were created to test the performance of mesh turbines and jet control systems using additive technologies. A methodological approach is proposed to create a classification of jet control systems considering their design and technological features. In the course of numerical experiments, the extreme conditions of fluid and gas outflow through a nozzle equipped with a velocity vector control system, in the control range of adjustment of the velocity vector deflection angle from + 90o to -90o within a geometric hemisphere, have been considered for the first time. It was also shown that when using a dual-channel nozzle, there are possibilities to adjust the velocity vector angle (thrust vector) in the range of + 180o to -180owithin the geometric sphere. Compared with the known variants, the control range of the velocity vector angle is increased by nine times. These calculated data are presented in addition to the previously published results of physical laboratory experiments. Preliminary results of numerical experiments show the possibility of creating a new theory in the field of mesh turbines and jet systems. Patents support the novelty of the developed technical solutions. Doi: 10.28991/esj-2021-01311 Full Text: PDF


Frequenz ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Francesco Centurelli ◽  
Pietro Monsurrò ◽  
Giuseppe Scotti ◽  
Pasquale Tommasino ◽  
Alessandro Trifiletti

Abstract Analysis, design, and characterization of an E-band Variable Gain Amplifier (VGA) in SiGe BiCMOS commercial technology is presented. VGA topologies are compared in terms of their capability to contribute to receiver linearity and dynamic range. The proposed VGA is based on a Gilbert multiplier cell exploiting current cancellation to enhance control range and linearity. A 1 dB bandwidth ranging from 80 to 100 GHz, a 24 dB gain control range and a −11.5 dBm input 1 dB compression point have been measured.


2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Lidan Mei ◽  
Nan Guo ◽  
Ling Li ◽  
Hongliang Zuo ◽  
Yan Zhao

AbstractTraditional glulam beam connection mode has a weak ability to transfer bending moment, leading to insufficient joint stiffness and mostly in the form of simply supported beams. To make full use of material strength, a novel prestressed glulam continuous beam was proposed. On this basis, this paper put forward a new method to further improve the mechanical performance of the beams by controlling prestress. According to the estimated ultimate loads of the beams, six different control range values were formulated, and 12 continuous beams were tested for flexural performance. The effects of prestressing control on the failure modes, ultimate load capacity, and load versus deformation relationships of the glulam continuous beams were analyzed. The test results indicated that the flexural performance of the beams with prestressed control was significantly improved compared to the uncontrolled beams, the ultimate load was enhanced by 13.60%–45.11%, and the average steel wire stress at failure was increased from 70% of the designed tensile strength to 94%. Combined with the finite element analysis (FEA), the reasonable control range of the prestressed control continuous beams was18%–30% of the estimated ultimate load. The research in this paper can provide references for the theoretical analysis and engineering application of similar structures.


Neurology ◽  
2021 ◽  
pp. 10.1212/WNL.0000000000012448
Author(s):  
Emma E. Wolters ◽  
Janne M. Papma ◽  
Sander C.J. Verfaillie ◽  
Denise Visser ◽  
Emma Weltings ◽  
...  

Objective:To assess the [18F]flortaucipir binding distribution across MAPT mutations in presymptomatic and symptomatic carriers.Methods:We compared regional [18F]flortaucipir binding potential(BPND) derived from a 130-minute dynamic [18F]flortaucipir PET scan, in nine (pre)symptomatic MAPT mutation carriers(4 with P301L[1 symptomatic], 2 with R406W[1 symptomatic]; 1 presymptomatic L315R, 1 presymptomatic S320F and 1 symptomatic G272V carrier) with 30 cognitively normal controls and 52 Alzheimer’s disease patients.Results:[18F]flortaucipir BPND images showed overall highest binding in the symptomatic carriers. This was most pronounced in the symptomatic R406W carrier in whom tau binding exceeded the normal control range in the anterior cingulate cortex, insula, amygdala, temporal, parietal and frontal lobe. Elevated medial temporal lobe BPND was observed in a presymptomatic R406W carrier. The single symptomatic and one of the three presymptomatic P301L carriers showed elevated [18F]flortaucipir BPND in the insula, parietal and frontal lobe compared to controls. The symptomatic G272V carrier exhibited a widespread elevated cortical BPND, with at neuropathological examination a combination of 3R pathology and encephalitis. The L315R presymptomatic mutation carrier showed higher frontal BPND compared to controls. The BPND values of the S320F presymptomatic mutation carrier fell within the range of controls.Conclusion:Presymptomatic MAPT mutation carriers already showed subtle elevated tau binding, whereas symptomatic MAPT mutation carriers showed a more marked increase in [18F]flortaucipir BPND. Tau deposition was most pronounced in R406W MAPT (pre)symptomatic mutation carriers, which is associated with both 3R and 4R tau accumulation. Thus, [18F]flortaucipir may serve as an early biomarker for MAPT mutation carriers in mutations that cause 3R/4R tauopathies.


Author(s):  
Pacharee Krongkitsiri ◽  
Wichai Krongkitsiri ◽  
Supakorn Phukird ◽  
Udom Tipparach

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Guangming Dai ◽  
Lihua Zhan ◽  
Chenglong Guan ◽  
Minghui Huang

Abstract In this study, the differential scanning calorimetry (DSC) tests were performed to measure the nonisothermal crystallization behavior of carbon fiber reinforced polyether ether ketone (CF/PEEK) composites under different cooling rates. The characteristic parameters of crystallization were obtained, and the nonisothermal crystallization model was established. The crystallization temperature range of the material at different cooling rates was predicted by the model. The unidirectional laminates were fabricated at different cooling rates in the crystallization temperature range. The results showed that the crystallization temperature range shifted to a lower temperature with the increase of cooling rate, the established nonisothermal crystallization model was consistent with the DSC test results. It is feasible to shorten the cooling control range from the whole process to the crystallization range. The crystallinity and transverse tensile strength declined significantly with the increase of the cooling rate in the crystallization temperature range. The research results provided theoretical support for the selection of cooling conditions and temperature control range, which could be applied to the thermoforming process of semi-crystalline polymer matrixed composites to improve the manufacturing efficiency.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Homero Ramírez ◽  
Aarón Isain Malendres-Álvarez ◽  
Alejandro Zermeño-González ◽  
Diana Jasso-Cantú ◽  
José ´Ángel Villarreal-Quintanilla

With the purpose to search upon the cytokinins origin, a study was conducted on the effects of prohexadione-ca (P-Ca) on cytokinins in xylem sap and on stomatal resistance in apple. Golden Delicious seedlings were sprayed with 100 ppm P-Ca. Stomatal leaf resistance was measured at intervals between 1 and 4 hours of spraying and 15 days after the treatment. Golden Delicious trees were sprayed with 200 ppm P-Ca two weeks after full bloom. At intervals between 1 and two weeks after P-Ca treatment, the main de-shooted stem was removed from root system and xylem sap was collected for cytokinins analysis using the suction technique. Prohexadioneca significantly increased stomatal resistance (range 2.74-4.35 s/cm−1) when compared to control (range 2.12-3.44 s/cm−1); however, P-Ca did not modify the level of cytokinins in xylem sap since range values were between 0.10 to 0.20 μg kinetin equivalents/20 ml xylem sap for both, cytokinin and control.    


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