A closed-loop scheme of a high-gain serial-parallel-switched-capacitor coupled-inductor (SPSCCI) boost DC-AC inverter is proposed by combining a two-phase generator and sinusoidal pulse-width-modulation (SPWM) control...
详细信息
ISBN:
(纸本)9789881404770
A closed-loop scheme of a high-gain serial-parallel-switched-capacitor coupled-inductor (SPSCCI) boost DC-AC inverter is proposed by combining a two-phase generator and sinusoidal pulse-width-modulation (SPWM) controller for low-power step-up DC-AC conversion and regulation. In this inverter, the power part is composed of SPSCCI booster and half-bridge DC-link. This booster is a 4-stage SC circuit plus combining a coupled-inductor, and it raises the voltage gain up to [4(n+1)+(1+nD)/(1-D)] at most via two-phase operation, where D is the duty cycle and n is the turn ratio of coupled-inductor. The DC-link is a half-bridge circuit in order to convert the DC voltage into AC via SPWM control for realizing the range of sinusoidal output: +0.5[4(n+1)+(1+nD)/(1-D)]VS~ -0.5[4(n+1)+(1+nD)/(1-D)]VS. Practically, the maximum output voltage can reach 26.0 times voltage of source VS while D=0.5, n=4. Here, the SPWM is employed to enhance regulation capability for the different output amplitude and frequency, as well as robustness to source/loading variation. Finally, the closed-loop SPSCCI inverter is designed and simulated by SPICE for some cases: steady-state and dynamic responses. All results are illustrated to show the efficacy of the proposed scheme.
A closed-loop scheme of a high-gain multiphase switched-capacitor coupled-inductor (MSCCI) converter is proposed by combining a phase generator and pulse-width-modulation-based (PWM-based) gain compensator for step-up...
详细信息
ISBN:
(纸本)9789881404770
A closed-loop scheme of a high-gain multiphase switched-capacitor coupled-inductor (MSCCI) converter is proposed by combining a phase generator and pulse-width-modulation-based (PWM-based) gain compensator for step-up DC-DC conversion and regulation. The power part between source VS and output VO contains a three-stage serial-parallel switched-capacitor (SC) circuit plus a coupled-inductor device, and it raises the voltage gain up to 4[(n+1)+(1+nD)/(1-D)] at most, where D means the duty cycle of PWM and n is trun ratio of coupled inductor. Practically, this MSCCI can boost the voltage gain up to 44 when D=0.5, n=4. Further, the PWM technique is adopted not only to enhance the output regulation for the compensation of the dynamic error between the practical and desired outputs, but also to reinforce output robustness against source or loading variation. Finally, the closed-loop MSCCI is designed by SPICE and simulated for some cases: steady-state and dynamic responses. All results are illustrated to show the efficacy of the proposed scheme.
Snakebite antivenom (SAV) is the standard treatment option to neutralize the toxic effects of snake venom, but their consequences on kidney function need to be better understood. This study aims to evaluate the effect...
详细信息
Snakebite antivenom (SAV) is the standard treatment option to neutralize the toxic effects of snake venom, but their consequences on kidney function need to be better understood. This study aims to evaluate the effects of antivenom on kidney and endothelial biomarkers due to Bothrops venom in two subgroups of patients distinguished by the presence of hemorrhagic syndrome at admission. This prospective study included 34 snakebite patients admitted to a tertiary hospital in Northeast Brazil between August 2019 and November 2020, 50 % of whom experienced spontaneous bleeding. Endothelial and kidney damage biomarkers were analyzed at three time points: before antivenom infusion and after 10 h and 20 h of antivenom infusion. Bleeding patients exhibited higher urine Neutrophil Gelatinase-Associated Lipocalin (uNGAL) and Kidney Injury Molecule-1 (KIM-1) levels, indicating incomplete renal recovery until 20h after antivenom. This group showed higher serum angiopoietin-2 (Ang-2) levels and vascular cell adhesion molecule-1 (VCAM-1). VCAM-1 levels positively correlated with kidney biomarker levels at each time point, especially after SAV. uNGAL was variant across VCAM-1, Ang-1, and Ang-2 levels before antivenom. Elevated levels of uNGAL and KIM-1, observed 10 h after SAV administration, may indicate incomplete renal protection and a potential risk for the development of chronic kidney injury, requiring future follow-up.
Wireless Sensor Networks (WSNs) consist of large number of sensor nodes with sensing, communication and computation capabilities. Sensor nodes have limited energy supply, bandwidth and computational capacity. Routing ...
详细信息
Wireless Sensor Networks (WSNs) consist of large number of sensor nodes with sensing, communication and computation capabilities. Sensor nodes have limited energy supply, bandwidth and computational capacity. Routing in sensor network differ based on the network architecture and the application in order to achieve high energy efficiency and better lifetime. In this paper, we have given the design issues of sensor network and also we classified the routing techniques into three main categories, flat, hierarchical and location based. We have described each routing techniques in appropriate category and presented a comparison of these routing techniques.
Electronic government, or e-Government, is the use of information and communication technology by the public sector (ICT). Additionally, it can be viewed as a paradigm shift in terms of how governments operate. The go...
详细信息
The goals of the paper were to describe were and find the relations between numbers of available public transportation and traffic congestion and other variables that can reduce traffic congestion in Jakarta. The data...
详细信息
In recent years, a lot of research concerns with the wireless sensor networks (WSN). With the increasing usages of WSN applications such as health care and disaster reporting, security requirements, wireless communica...
详细信息
As the use of digital television (D-TV) has spread across the globe, usability problems on D-TV have become an important issue. However, so far, very little has been done in the usability studies on D-TV. The aim of t...
详细信息
Propranolol hydrochloride can be considered a persistent and bioaccumulative pharmaceutical in the *** drug and its by-products are potentially toxic and have adverse effects,since these compounds have been associated...
详细信息
Propranolol hydrochloride can be considered a persistent and bioaccumulative pharmaceutical in the *** drug and its by-products are potentially toxic and have adverse effects,since these compounds have been associated with endocrine-disrupting effects,reproductive deficiencies,embryo abnormalities and pericardial ***_(2)–La 0.05%–carboxymethyl-β-cyclodextrin(CMCD)nanoparticles were successfully prepared by a simple two-step method,which consists of sonification and *** characterization analyses reveal that lanthanum is dispersed on the semiconductor surface,probably forming Ti–O–La bonds,which can induce oxygen vacancies and surface defects that effectively restrain the recombination of photogenerated electron/holes *** efficiency of TiO_(2)–La 0.05%–CMCD samples in degradation of propranolol under UV-light irradiation is higher than that of pristine TiO_(2) within 20 min reaction,probably due to complex formation between theβ-blocker and the oligosaccharide,which allows us to propose a photocatalytic mechanism based on the formation of intermediates and competition of these compounds to the radicals and CMCD cavities.
Factor analysis is used to reduce data or summarize, from the old variable which is widely changed to a few new variables called factors, and still contains most of the information contained in the original variable. ...
详细信息
暂无评论