Power distribution systems must be very effective in power delivery. Utilities are continuously looking for recent technologies to enhance power delivery performance. The control of power loss is one ...of the most important issues directly related to system efficiency. Distribution system reconfiguration and optimal capacitor placement are the two most popular techniques adapted for the control of power loss. The techniques not only concentrate on power loss control but also control volt/var of the distribution system, and at the same time improve the system reliability and security. Former method is the process of changing the topology of distribution system by altering the open/closed status of switches to find a radial operating structure that minimizes the system real power loss while satisfying operating constraints. Later is the identification of optimal location and size of the capacitors with the objective of minimizing the power loss. This paper combines both reconfiguration and optimal capacitor placement for the effective optimization. Furthermore, it utilizes Opposition based Differential Evolution algorithm for efficient searching for the optimal solution. The effectiveness of the proposed approach is demonstrated by employing the feeder switching operation scheme to IEEE-33 bus Power Distribution systems. The proposed algorithm reduces the transmission loss and controls volt/var while satisfying power flow constraints.
Distributivne energetske sustav mora biti vrlo učinkovit u prijenosu energije. Javni sektor neprestano traga za novim tehnologijama ne bi li povećao učinkovitost prijenosa. Upravljanje gubicima ...energije jedan je od najvažnijih problema koji je direktno povezan s učinkovitošću mreže. Rekonfiguracija distributivne mreže i optimalno pozicioniranje kondenzatora su dvije uvriježene metode koje su prilagođene za upravljanje gubicima energije. Navedene metode se ne koncentriraju samo na upravljanje gubicima već i upravljaju naponsko-reaktivnim prilikama distributivne mreže, i istovremeno povećavaju raspoloživost i pouzdanost sustava. Prva metoda uključuje postupak promjene topologije distributivne mreže promjenom stanja sklopki kako bi se našla radijalna operativna struktura koja minimizira gubitke radne snage u prijenosu uz zadovoljenje operativnih ograničenja. Druga metoda uključuje identifikaciju optimalne lokacije i veličine kondenzatora s ciljem minimizacije gubitaka snage. U ovom radu se kombiniraju obje metode, rekonfiguracije i optimalnog pozicioniranja, s ciljem učinkovite optimizacije. Za postupak optimizacije odabran je na opoziciji baziran genetski algoritam diferencijske evolucije s ciljem učinkovite pretrage optimalnog rješenja. Učinkovitost predloženog pristupa provjerena je primjenom komutacijske sheme srednjenaponske distributivne mreže na IEEE-33 sabirnici baziranim distributivnim energetskim sustavima. Predloženi algoritam smanjuje gubitke prijenosa i upravlja naponsko-reaktivnim prilikama mreže uz zadovoljenje ograničenja na tokove energije.
Background:
Acute coronary syndrome (ACS) continues to be a leading cause of morbidity and mortality worldwide. Galectin-3 and pentraxin-3 are two prognostic biomarkers that have been studied in ...heart failure (HF). However, there are limited data on these biomarkers in the ACS population. The objective of the study was to determine the variables that are most affected by high concentrations of pentraxin-3 and galectin-3, and the influence they have on outcomes of all-cause mortality in patients with ACS.
Methods:
We included a total of 160 patients ST elevation myocardial infarction (STEMI),n = 64; non STEMI/unstable angina (NSTEMI/UA), n = 38; and control subjects with chronic stable angina (CSA)/microvascular angina (MVA) n = 58. Plasma pentraxin-3 and galectin-3 levels were assessed from these patients at the time of hospital admission. Major adverse cardiovascular events including all-cause mortality, rehospitalizations and coronary artery bypass graft surgery (CABG) were assessed at 6 months.
Results:
The median concentration of pentraxin-3 and galectin-3 were significantly higher in STEMI than in NSTEMI patients (p < 0.005) or controls (p < 0.005). Greater numbers of deaths (4 versus 0) were observed in STEMI patients with higher levels of these biomarkers. In addition, ACS patients with high levels of pentraxin-3 and galectin-3 had lower left ventricular ejection fraction (LVEF) (p < 0.005), and a moderate correlation was observed between LVEF and pentraxin-3 levels (r = -0.45, p < 0.005). Patients with higher galectin-3 levels were also observed to have a lower estimated glomerular fraction rate (eGFR), and a moderate correlation was observed between them (r = -0.34, p < 0.005).
Conclusion:
Pentraxin-3 and galectin-3 hold much promise in the ACS population as prognostic biomarkers.
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