다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

비만아 부모의 돌봄 경험: q 방법론

Wide band gap semiconductors are essential for today's electronic devices and energy applications because of their high optical transparency, controllable carrier concentration, and tunable electrical conductivity. The most intensively investigated wide band gap semiconductors are transparent conductive oxides (TCOs), such as tin-doped indium oxide (ITO) and amorphous In-Ga-Zn-O (IGZO), used in displays and solar cells, carbides (e.g., SiC) and nitrides (e.g., GaN) used in power electronics, and emerging halides (e.g., γ-CuI) and 2D electronic materials (e.g., graphene) used in various optoelectronic devices. Compared to these prominent materials families, chalcogen-based (Ch = S, Se, Te) wide band gap semiconductors are less heavily investigated but stand out because of their propensity for p-type doping, high mobilities, high valence band positions (i.e., low ionization potentials), and broad applications in electronic devices such as CdTe solar cells. This manuscript provides a review of wide band gap chalcogenide semiconductors. First, we outline general materials design parameters of high performing transparent semiconductors, as well as the theoretical and experimental underpinnings of the corresponding research methods. We proceed to summarize progress in wide band gap (EG > 2 eV) chalcogenide materials-namely, II-VI MCh binaries, CuMCh2 chalcopyrites, Cu3MCh4 sulvanites, mixed-anion layered CuMCh(O,F), and 2D materials-and discuss computational predictions of potential new candidates in this family, highlighting their optical and electrical properties. We finally review applications-for example, photovoltaic and photoelectrochemical solar cells, transistors, and light emitting diodes-that employ wide band gap chalcogenides as either an active or passive layer. By examining, categorizing, and discussing prospective directions in wide band gap chalcogenides, this Review aims to inspire continued research on this emerging class of transparent semiconductors and thereby enable future innovations for optoelectronic devices.

https://escholarship.org/content/qt1xf1k15d/qt1xf1k15d.pdf?t=qof0vs

Wide Band Gap Chalcogenide Semiconductors.

The degradation of photovoltaic (PV) systems is one of the key factors to address in order to reduce the cost of the electricity produced by increasing the operational lifetime of PV systems. To reduce the degradation, it is imperative to know the degradation and failure phenomena. This review article has been prepared to present an overview of the state-of-the-art knowledge on the reliability of PV modules. Whilst the most common technology today is mono- and multi-crystalline silicon, this article aims to give a generic summary which is relevant for a wider range of photovoltaic technologies including cadmium telluride, copper indium gallium selenide and emerging low-cost high-efficiency technologies. The review consists of three parts: firstly, a brief contextual summary about reliability metrics and how reliability is measured. Secondly, a summary of the main stress factors and how they influence module degradation. Finally, a detailed review of degradation and failure modes, which has been partitioned by the individual component within a PV module. This section connects the degradation phenomena and failure modes to the module component, and its effects on the PV system. Building on this knowledge, strategies to improve the operational lifetime of PV systems and thus, to reduce the electricity cost can be devised. Through extensive testing and failure analysis, researchers now have a much better overview of stressors and their impact on long term stability. • Review of reliability metrics and test methodologies for photovoltaic modules • Indicative mapping of relationships between stressors, components, failures and effects in PV modules. • Assessment on the impact of degradation and failure on LCOE and EPBT. • Review of design considerations for all components in a PV module regarding reliability. 

Review of degradation and failure phenomena in photovoltaic modules

Insights into kesterite's back contact interface: A status review

Copper Indium Gallium Selenide- (CIGS-) based solar cells have become one of the most promising candidates among the thin film technologies for solar power generation The current record efficiency of CIGS has reached 226% which is comparable to the crystalline silicon- (c-Si-) based solar cells However, material properties and efficiency on small area devices are crucial aspects to be considered before manufacturing into large scale The process for each layer of the CIGS solar cells, including the type of substrate used and deposition condition for the molybdenum back contact, will give a direct impact to the efficiency of the fabricated device In this paper, brief introduction on the production, efficiency, etc of a-Si, CdTe, and CIGS thin film solar cells and c-Si solar cells are first reviewed, followed by the recent progress of substrates Different deposition techniques’ influence on the properties of molybdenum back contact for CIGS are discussed Then, the formation and thickness influence factors of the interfacial MoSe2 layer are reviewed; its role in forming ohmic contact, possible detrimental effects, and characterization of the barrier layers are specified Scale-up challenges/issues of CIGS module production are also presented to give an insight into commercializing CIGS solar cells

/pdf/review-on-substrate-and-molybdenum-back-contact-in-cigs-thin-37ofb648op.pdf

Review on Substrate and Molybdenum Back Contact in CIGS Thin Film Solar Cell

Electric supply is listed as one of the basic amenities of sustainable development in Malaysia. Under this key contributing factor, the sustainable development goal aims to ensure universal access to an affordable, clean, and reliable energy service. To support the generation capacity in years to come, distributed generation is conceptualized through stages upon its implementation in the power system network. However, the rapid establishment growth of distributed generation technology in Malaysia will invoke power quality problems in the current power system network. In order to prevent this, the current government is committed to embark on the development of renewable technologies with the assurance of maintaining the quality of power delivered to consumers. Therefore, this research paper will focus on the review of the energy prospect of both fossil fuel and renewable energy generation in Malaysia and other countries, followed by power quality issues and compensation device under a high renewable penetration distribution network. The issues and challenges of distributed generation are presented, with a comprehensive discussion and insightful recommendation on future work of the distributed generation. In accordance with the addressed highlights in this paper, it would serve as the criterion on upcoming revolution of distributed generation integrated along with the traditional network in Malaysia.

https://www.mdpi.com/1996-1073/13/24/6479/pdf

Distributed Generation: A Review on Current Energy Status, Grid-Interconnected PQ Issues, and Implementation Constraints of DG in Malaysia

As part of the device fabrication process, selenization step is required to crystallise the CIGS absorber layer. However, during high temperature selenization process, excessive formation of MoSe2 ...

/pdf/formation-of-moox-barrier-layer-under-atmospheric-based-31nnshj044.pdf

Formation of MoOx barrier layer under atmospheric based condition to control MoSe2 formation in CIGS thin film solar cell

This paper proposed two PWM control scheme which is the Voltage Oriented Control (VOC) and Direct Power Control (DPC) on a heavy loaded LV-distribution network with photovoltaic (PV) integration in Malaysia. The surge in demand of power supply is overcome by deploying more PV to fulfil the load demand. However, this could give rise to power quality issues that can affect the stability of the grid. The focus in this work is to solve voltage dynamic concern which results in over and undervoltage problems within the distribution network and at the same time to evaluate on the performance of both control schemes under a heavy loaded condition. A 33 kV Malaysian LV-Distribution model integrated with PV is constructed to serve as a base model in this paper. From the base model, a load flow analysis is conducted in order to locate the weakest bus. The two proposed control schemes are introduced into the weakest bus in the grid system, and its performance of the controller will be evaluated based on three aspects such as compensation margin, voltage and current total harmonics distortion (vTHD and iTHD) and lastly the compensated voltage levels. It is shown that VOC control scheme has outperformed DPC due to a wider compensation margin and its ability to achieve the desired reference voltage with a faster settling time under heavy loaded condition. Therefore, the proposed PWM control scheme of both VOC and DPC under a heavy load scenario could be set as a benchmark to provide impactful insights and findings towards an actual implementation of the application within a distribution network or distributed generation.

Voltage Oriented Control and Direct Power Control Strategies in solving under and overvoltage conditions for heavy load application on Malaysian Distribution Representative Network

Kam Hoe Ong

Papers

Review on Substrate and Molybdenum Back Contact in CIGS Thin Film Solar Cell

Distributed Generation: A Review on Current Energy Status, Grid-Interconnected PQ Issues, and Implementation Constraints of DG in Malaysia

Formation of MoOx barrier layer under atmospheric based condition to control MoSe2 formation in CIGS thin film solar cell

Voltage Oriented Control and Direct Power Control Strategies in solving under and overvoltage conditions for heavy load application on Malaysian Distribution Representative Network

Energy storage systems: A review of its progress and outlook, potential benefits, barriers and solutions within the Malaysian distribution network