An improved three-level direct torque control method of brushless doubly-fed machine based on the fixed synthesizing vector

With the rapid growth of an AC adjusted speedsystem application, it is necessary to controland reduce harmonic pollution since theproblem brought about by the device of powerelectronics not only blocks the development ofpower electronics technology, but also causessevere harm in an electric power system. In thispaper an improved three-level direct torquealgorithm for brushless doubly-fed machines hasbeen developed for reducing the torque and fluxripples in a brushless doubly-fed machine. Thismethod based on 48 fixed synthesizing vectors isimplemented in the brushless doubly-fed machine.Compared with the traditional two-level directtorque control algorithm, this new methodbroadens the selection range on voltage vectors. Italso effectively reduces the torque ripples andimproves the properties of the magnetic chaintrack. In addition, this algorithm improves thedynamic performance and robustness of both thebrushless doubly-fed machine and its controlsystem. To validate the proposed method, somemathematic simulations have been done so that thesimulation results have shown the effectiveness ofthe proposed method. Moreover, this proposedmethod has been implemented in the brushlessdoubly-fed machine system showing anenhancement in the motor performance

Solar full-disk magnetic field image receiving system and observation software

The paper introduces terminal hardware system of 10 cm high resolution full-disk magnetic field telescope among solar multi-channel telescope produced by Beijing Astronomical Observatory, and its software procedure by using imaging processing as well real time data collecting. These data were processed by Sun Workstation 470/4, including doing some spectrum analysis, the system is unique in the world now. It uses a set of CCD (1320 pixels plus 1035 pixels) of high resolution image explosion, also it has a set of fast and high resolution (1024 pixel plus 1024 pixel) image processor. Moreover, we can obtain higher time and space resolution about solar full-disk magnetic field and velocity field. This will provide excellent means in observation and studies of full-disk solar large-scale magnetic field and velocity field

Oś MIF/CD74 jako cel terapii metforminą w podocytopatii cukrzycowej — rzeczywista praktyka kliniczna

Introduction：To observe the effects of metformin on urinary excretion of MIF, CD74 and podocalyxin in type 2 diabetics and to explore its possible renoprotective mechanisms. Methods: 202 uncontrolled type 2 diabetics, who were previously prescribed sulfonylurea monotherapy(n=100) or sulfonylurea in combination with metformin (n=102) were enrolled in the study. The amount of macrophage migration inhibitory factor(MIF) and CD74 in serum, urinary MIF to creatine ratio(UMCR), urinary CD74 to creatine ratio(UCCR), urinary albumin to creatine ratio(UACR) and urinary podocalyxin to creatine ratio (UPCR) were determined. Results: Metabolic parameters including fasting blood glucose, postprandial 2 hours blood glucose, hemoglobin A1c, MIF and CD74 in serum were comparable between the two groups. Moreover, metformin add-on therapy showed significantly better efficacy in reducing UMCR, UCCR, UPCR and UACR in comparison with those in sulfonylurea monotherapy group, respectively. UPCR had positive correlation with UACR, UMCR and UCCR (r＝0.73, r=0.69, r=0.62, P < 0.01), respectively. Conclusions: Metformin could present its podocyte-protective capacity in type 2 diabetics and the underlying mechanisms may be partly attributed to its effects in suppressing MIF-CD74 axis mediated inflammatory cascade response. Wstęp: Celem pracy było zaobserwowanie efektów działania metforminy na wydalanie MIF, CD74 i podokaliksyny w moczu pacjentów z cukrzycą typu 2 oraz zbadanie jej możliwych mechanizmów nefroprotekcyjnych. Materiał i metody: W badaniu wzięło udział 202 pacjentów z niewyrównaną cukrzycą typu 2, którym zalecono wcześniej monoterapię sulfonylomocznikiem (n = 100) lub sulfonylomocznikiem skojarzonym z metforminą (n = 102). Podczas badania określono ilość czynnika hamującego migrację makrofagów (MIF) i CD74 w surowicy krwi, wskaźnik MIF/kreatynina (urinary MIF to creatinine ratio; UMCR), wskaźnik CD74/kreatynina (urinary CD74 to creatinine ratio; UCCR), wskaźnik albumina/kreatynina (urinary albumin to creatinine ratio; UACR) oraz wskaźnik podokaliksyna/kreatynina (urinary podocalyxin to creatinine ratio; UPCR). Wyniki: Parametry metaboliczne, w tym glikemia na czczo, stężenie glukozy we krwi dwie godziny po posiłku, hemoglobina A1c, MIF i CD74 w surowicy krwi były porównywalne w obu grupach. Ponadto, terapia z dodatkiem metforminy wykazała znacznie lepszą skuteczność w redukowaniu wskaźników UMCR, UCCR, UPCR i UACR w porównaniu z grupą, w której zastosowano monoterapię sulfonylomocznikiem. Wskaźnik UPRC wykazywał dodatnią korelację ze wskaźnikami UACR, UMCR i UCCR (odpowiednio: r = 0,73, r = 0,69, r = 0,62, p &lt; 0,01). Wnioski: Metformina może wykazywać zdolność do ochrony podocytów u pacjentów z cukrzycą typu 2, a mechanizmy leżące u pod­staw tego procesu mogą być częściowo przypisane jej właściwościom hamowania kaskady reakcji zapalnych zależnych od osi MIF-CD74

A novel statistical method for long-term coronavirus modelling

Background: Novel coronavirus disease has been recently a concern for worldwide public health. To determine epidemic rate probability at any time in any region of interest, one needs efficient bio-system reliability approach, particularly suitable for multi-regional environmental and health systems, observed over a sufficient period of time, resulting in a reliable long-term forecast of novel coronavirus infection rate. Traditional statistical methods dealing with temporal observations of multi-regional processes do not have the multi-dimensionality advantage, that suggested methodology offers, namely dealing efficiently with multiple regions at the same time and accounting for cross-correlations between different regional observations. Methods: Modern multi-dimensional novel statistical method was directly applied to raw clinical data, able to deal with territorial mapping. Novel reliability method based on statistical extreme value theory has been suggested to deal with challenging epidemic forecast. Authors used MATLAB optimization software. Results: This paper described a novel bio-system reliability approach, particularly suitable for multi-country environmental and health systems, observed over a sufficient period of time, resulting in a reliable long-term forecast of extreme novel coronavirus death rate probability. Namely, accurate maximum recorded patient numbers are predicted for the years to come for the analyzed provinces. Conclusions: The suggested method performed well by supplying not only an estimate but 95% confidence interval as well. Note that suggested methodology is not limited to any specific epidemics or any specific terrain, namely its truly general. The only assumption and limitation is bio-system stationarity, alternatively trend analysis should be performed first. The suggested methodology can be used in various public health applications, based on their clinical survey data.publishedVersio