Bridgeless Isolated AC LED Driver

A novel bridgeless isolated AC LED driver is developed, which improves LED utilization and application flexibility due to a coupled inductor inserted between the bidirectional switch and the LED module without any output electrolytic capacitor. By reducing the turns ratio of the coupled inductor, the voltage across the secondary side will be decreased so as to lessen the voltage across the LED strings and hence reduce the number of LEDs, thereby making the load design of the AC LED driver more flexible. It is noted that the coupled inductor plays a role of not only galvanic isolation but also inductor behavior as well as transformer behavior. Therefore, during the turn-on period of the bidirectional switch, the coupled inductor can transfer the energy to one LED string and store the energy simultaneously, whereas during the turn-off period of the bidirectional switch, the coupled inductor can release the stored energy to the other LED string. That is, two LED strings are conducted over a pulse-width-modulated (PWM) period for any half-cycle, implying that LED utilization is upgraded. As for LED dimming, it is realized by directly tuning the control signal for the bidirectional switch without any dimming circuit. Eventually, the basic operating principles and theoretical deductions are given along with some experimental results provided to verify the effectiveness of the proposed AC LED driver topology.

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Peran Bank Syariah: Menuju Perekonomian Masyarakat Madani

Mabsya: Jurnal Manajemen Bisnis Syariah ◽

10.24090/mabsya.v1i2.3461 ◽

2019 ◽

Vol 1 (2) ◽

pp. 131-144

Author(s):

Dini Maulana Lestari ◽

M Roif Muntaha ◽

Immawan Azhar BA

Keyword(s):

Financial Markets ◽

Islamic Law ◽

Financial Service ◽

Islamic Banks ◽

Free Society ◽

The Public ◽

Turn On ◽

The People ◽

Strategic Role

Islamic banks are present in the community as financial institutions whose activities are based on the principles of Islamic law for the benefit of the people. This study aims to determine the strategic role of Islamic Banks as financial service institutions, the importance of the existence of Islamic Banks and Islamic-based markets and financial instruments in them. In its development, Islamic banks have a role as institutions that turn on public funds, channel funds to the public, transfer assets, liquidity, reallocation of income and transactions. In the Indonesian economic system, the existence of Islamic Banks is important as an alternative solution to the problem of conflict between bank interest and usury. Islamic financial markets and instruments provide a free society of interest and follow a different set of principles. Distribution of profit/ loss according to evidence of participation in the management fund. The division of rental income in the form of musharaka.

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Dual role of silver in a fluorogenic N-squaraine probe based on Ag(I)-π interactions

Dalton Transactions ◽

10.1039/d1dt01408k ◽

2021 ◽

Author(s):

Manel Vega ◽

Salvador Blasco ◽

Enrique García-España ◽

Bartolome Soberats ◽

Antonio Frontera ◽

...

Keyword(s):

Dft Calculations ◽

Experimental Evidence ◽

Dual Role ◽

Π Interactions ◽

Turn On

In the presence of Ag(I), the monoanion of a cyano-N-squaraine (I) generates an intense fluorescent turn-on response. Experimental evidence and DFT calculations reveal a sequence of deprotonation-coordination events in which...

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LED Driver Achieves Electrolytic Capacitor-Less and Flicker-Free Operation with an Energy Buffer Unit

2018 IEEE Energy Conversion Congress and Exposition (ECCE) ◽

10.1109/ecce.2018.8558053 ◽

2018 ◽

Cited By ~ 2

Author(s):

Peng Fang ◽

Bo Sheng ◽

Yan-Fei Liu ◽

Yan Zhang

Keyword(s):

Electrolytic Capacitor ◽

Led Driver ◽

Energy Buffer

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Pendekatan Historis Kristis Terhadap Bilangan 3 dan 4 tentang Tanggung Jawab Pendeta

BIA': Jurnal Teologi dan Pendidikan Kristen Kontekstual ◽

10.34307/b.v2i2.133 ◽

2019 ◽

Vol 2 (2) ◽

pp. 209-222

Author(s):

Astin Mangean

Keyword(s):

Turn On ◽

Critical History ◽

Library Research

The tribe of Levi was chosen and ordained by God for hold whorsip in tabernacle of the congregation. Their work is simple but they must to do accordingly with their role in Number 3 and 4 and exactly that God command. To investigate and review the Number 3 and 4, the author uses critical history method by putting attention to the situation in the text and the situation gave the text. The role of the tribe of Levi is offer sacrifices and pray, interpretation the urim dan tumim, difference between holy and unholy and between clean and unclean, turn on the lamps, blowing of trumpets, unload, transport and rebuild the tabernacle. When the tribe of Levi doing the role they must maintain holiness in front of God. Based on that role then the life of tribe of Levi can be a reference for life of priest it mainly concerns the role of serving the Lord.Abstrak: Suku Lewi dipilih dan ditetapkan oleh Tuhan untuk menyelenggarakan ibadat di kemah suci. Mereka harus melaksanakannya sesuai yang diperintahkan Tuhan. Kajian terhadap peran suku Lewi dalam Bilangan 3 dan 4 ini menggunakan metode penelitian kepustakaan (Library research) dengan pendekatan kritik historis. Metode ini menaruh perhatian pada situasi yang digambarkan dalam teks dan situasi yang melahirkan teks. Adapun peran suku Lewi yakni mempersembahkan korban-korban serta menaikan doa, menafsirkan urim dan tumim, harus dapat membedakan kudus dan tidak kudus, najis dan tidak najis, menyalakan kandil, meniup serunai perak, memberikan berkat dalam nama Allah, penasehat umat, menjaga kemah suci, membongkar, mengangkut dan mendirikan kembali kemah suci. Ketika melaksanakan peran tersebut suku Lewi harus tetap menjaga kekudusan hidupnya dihadapan Tuhan. Berdasarkan peran tersebut, maka kehidupan suku Lewi dapat menjadi acuan bagi kehidupan pendeta masa kini terutama menyangkut peran sebagai pelayan Tuhan.

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Hydraulic Control of a Buck Converter

10.1115/fpmc2021-68682 ◽

2021 ◽

Author(s):

Rudolf Scheidl

Keyword(s):

Buck Converter ◽

Hydraulic Control ◽

Simple Analytical Model ◽

Operating Characteristics ◽

Response Dynamics ◽

Output Pressure ◽

Operation Conditions ◽

Basic Operating ◽

Periodic Switching

Abstract This paper investigates a concept for the pure hydraulic control of a buck converter using a hydraulically piloted 2-2 way on-off valve. The pilot system is controlled by the desired output pressure of the buck converter in form of a pressure signal and the RC filtered feedback of the actual pressure. These pressures act via small plunger cylinders in opposite direction on the on-off valve. An additional pilot cylinder features a jumping active hydraulic area for a robust feedback. The valve performs close to rectangular oscillations, the frequency of which is mainly determined by the characteristic time of the RC filter. The concept is studied by a simple analytical model to obtain its basic operating characteristics and by a detailed numerical model to analyze the role of parasitic effects on system performance. The paper shows that this concept works and can robustly follow the commanded output pressure. The converter has a moderate response dynamics; in certain operation conditions it shows an aperiodic behavior by alternating between phases of periodic switching and pause.

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Insights from vaccinia virus into Toll-like receptor signalling proteins and their regulation by ubiquitin: role of IRAK-2

Biochemical Society Transactions ◽

10.1042/bst0360449 ◽

2008 ◽

Vol 36 (3) ◽

pp. 449-452 ◽

Cited By ~ 8

Author(s):

Andrew G. Bowie

Keyword(s):

Vaccinia Virus ◽

Interleukin 1 ◽

Nuclear Factor Κb ◽

Tumour Necrosis Factor Receptor ◽

Relative Role ◽

Toll Like Receptor ◽

Turn On ◽

Receptor Signalling ◽

Necrosis Factor

TLRs (Toll-like receptors) are an important class of pathogen-sensing proteins, which signal the presence of a pathogen by activating transcription factors, such as NF-κB (nuclear factor κB). The TLR pathway to NF-κB activation involves multiple phosphorylation and ubiquitination events. Notably, TRAF-6 [TNF (tumour necrosis factor)-receptor-associated factor-6] Lys63 polyubiquitination is a critical step in the formation of signalling complexes, which turn on NF-κB. Here, the relative role of different IRAKs [IL-1 (interleukin 1)-receptor-associated kinases] in NF-κB activation is discussed. Further, I demonstrate how understanding one molecular mechanism whereby vaccinia virus inhibits NF-κB activation has led to a revealing of a key role for IRAK-2 in TRAF-6-mediated NF-κB activation.

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