1,720,967 research outputs found
Temperature Cycling Test on Ultrasonic Aluminum Bonds and Conductive Adhesive of Copper Indium Gallium (di)Selenide (CIGS) Thin-Film Photovoltaic Solar Panel
No full textThis work assesses the bondability and temperature cycling reliability of ultrasonic Al bonds on Molybdenum (Mo) and Molybdenum (di)Selenide (MoSe2) layers of a Copper Indium Gallium (di)Selenide (CIGS) thin-film photovoltaic (TFPV) solar panel. The bondability and reliability of ultrasonic Al bonds were assessed using a qualitative load-displacement profile and quantitative peel force data obtained from a peel test, as well as contact resistance R-c measured using the transmission line method. It was discovered that using the peel test to examine the bondability and reliability of ultrasonic Al bonds and conductive adhesives was quite beneficial. Varied forms of ultrasonic Al bonds and conductive adhesives, either on Mo or MoSe2 layers, have different shapes of load-displacement profiles before and after the application of temperature cycling. Therefore, comparing the load-displacement profile, peel force, and R-c could offer a complete bonding mechanism, failure modes, and failure mechanism for ultrasonic Al bond on MoSe2 and Mo layers of CIGS TFPV solar panels before and after temperature cycling.Ministry of Higher Education of Malaysia
Fundamental Research Grant Scheme (Grant Number: FRGS/1/2020/TKO/UNIKL/02/10)
10.13039/501100009848-Universiti Kuala Lumpur (Grant Number: str19087
Effect of ultrasonic bonding and lamination on electrical performance of copper indium gallium (de)Selenide CIGS thin film photovoltaic solar panel
No full textThis paper aims to study the effect of ultrasonic aluminum (Al) bonding and lamination processes on the electrical performance of copper indium gallium (di)selenide (CIGS) thin film photovoltaic (TFPV) solar panels. Ultrasonic Al bonding on the MoSe2 layer of the CIGS TFPV solar panel was performed in three configurations: eight bonds, 16 bonds, and parallel configurations. The lamination process was performed on the Al bonds with MoSe2 layers of the CIGS TFPV solar panel. Ultrasonic bonding and lamination processes significantly affect the electrical performance of CIGS TFPV solar panels. Open circuit voltage, Voc is the least affected electrical characteristic with the application of ultrasonic bonding and lamination processes as compared to short circuit current (Isc), current density (Jsc), maximum power (Pmpp), fill factor (FF), and efficiency. 8-bonds configuration has the highest efficiency, ranging from 11.45% to 13.86% throughout unique connections of I-V measurement, compared to 16-bonds ranging from 7.99% to 10.77%, and parallel configurations, ranging from 9.14% to 11.92%. The notable variations in electrical properties with the processes used to create laminated CIGS TPFV solar panels with ultrasonic Al bonding can be explained by physical examination and lock-in infrared (IR) thermography. The ultrasonic Al bond is best suited to be used as the interconnection mean in the CIGS TFPV solar panel compared to that of conductive adhesive that has been widely applied nowadays.This work was sponsored by the Ministry of Higher Education of Malaysia under the Fundamental Research Grant Scheme [FRGS/1/2020/TKO/UNIKL/02/10] and Universiti Kuala Lumpur under Short Term Research Grant [str19087]
Bondability of ultrasonic Aluminum bonds on the molybdenum (de) selenide and molybdenum of back contact layer of copper indium gallium (de)selenide GIGS thin film photovoltaic solar panel
No full textThis paper aims to study the bondability of ultrasonic Aluminum, Al bonds on Mo and MoSe2 layers of back-contact metal of copper indium gallium (de)selenide (CIGS) thin film photovoltaic (TFPV) solar panel. The bondability of ultrasonic Al bonds were evaluated based on the contact resistance, R-c, peel strength and electrical characteristics measured using transmission line method (TLM), peel test, and current-voltage (I-V) measurement, respectively. Besides, the qualitative results of load-distance profiles from tensile test also have been used to evaluate the bondability of the ultrasonic Al bonds. Two type of lamination constructions namely construction 1 and construction 2 were built on the CIGS TPFV solar panel with ultrasonic Al bonds on Mo and MoSe2. It was noted that the new method of removing CIGS layer up until MoSe2 is the plausible technique to be used. Ultrasonic Al bond on Mo layer has higher bondability as compared to that of ultrasonic Al bond on MoSe2 through the quantitative results of R-c, peel strength and qualitative result of load-distance profile. CIGS TFPV solar panel with construction 2 is the suitable construction for the CIGS TFPV solar panel due to the higher rigidity, and even stress distribution experienced during lamination process as compared to that of construction 1. It is noted that steps taken from ultrasonic bonding until lamination process has increased the cumulative contact area and decreased the R-c and consequently increased the efficiency of CIGS TFPV solar panel with ultrasonic Al bond on MoSe2 layer.This work was sponsored by Ministry of Higher Education of Malaysia under the Fundamental Research Grant Scheme (FRGS/1/ 2020/TKO/UNIKL/02/10) and Universiti Kuala Lumpur under Short
Term Research Grant (str19087)
Ultrasonic Al Bond on Mo Back-Contact Layer of CIGS Solar Panel Characterization Using Infinite Focus Microscope (IFM) and Micro-Ohmmeter
No full textThe aim of this study is to identify the bonding mechanisms of the ultrasonic Al bond on the Mo back-contact layer (Al-Mo system) of a copper indium gallium (de) selenide (CIGS) thin-film photovoltaic (TFPV) solar panel. The bonding mechanism of the Al-Mo system was obtained from the identification of nonstick footprints of Al ribbon and the deformation of ultrasonic Al bonds on the Mo layer using an infinite focus microscope (IFM). The effect of Al bond deformation toward the bondability and electrical behavior of the bonds was evaluated by comparing the results obtained from IFM with the peel force, contact resistance from the transmission line method (TLM), and resistance from a micro-ohmmeter, respectively. It is observed that ultrasonic bonding parameters have a major impact on the deformation, bondability, and electrical properties of ultrasonic Al bonds on Mo layers. The bonding mechanism and failure mode can be identified through the IFM examination through the formation of footprints and the evolution of microwelds (remnant) of ultrasonic Al bonds and the occurrence of glass substrate cratering. It was found that arithmetical mean deviation of the assessed profile (R a) of more than 6 µm indicates that the ultrasonic Al bond has been formed on the Mo layer. The contact resistance values are more toward representing the variation of intimate contact area, while resistance is more toward representing the resistance of two bonds and the straightness of the Al ribbon
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Superluminal Geometrodynamics of Braneworld Hyperdrive via Brane-Bulk Interaction
Full text linkAlcubierre warp-drive was first to introduce superluminal travel from
different approach. Instead of creating short cut through spacetime via a
wormhole, geometrodynamics of simultaneously contract and expand spacetime were
conjectured. However, both methods require exotic matter that violate energy
condition. In this paper we employ the concept of braneworld that naturally
influence spacetime geometrodynamics. Start from define and develop the
spacetime metric of braneworld warp bubble, the expression for energy densities
as function of relevant parameters which contribute to the braneworld approach
of superluminal travel by hyperspace-drive were deriveComment: 15 pages, 9 figure
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
