Application of Electronics Packaging Fundamentals to Photovoltaic Interconnects and Packaging

2019 ◽  
Author(s):  
Laura Spinella ◽  
Nick Bosco
Keyword(s):  
Electronics Packaging ◽  
Test Time ◽  
Reliability Models ◽  
Current State ◽  
Pv Module ◽  
Analytical Reliability ◽  
Standard Module ◽  
Model Size ◽  
Natural Climate ◽  
Physical Phenomena

Abstract The energy capacity of photovoltaic (PV) installations worldwide has increased significantly in the last decade, increasing the demand for rigorous investigation of the physical phenomena causing degradation and failures in PV modules. As PV reliability science develops, established methods and approaches from longer-standing industries can inform and expedite PV reliability advances. This work demonstrates how thermomechanical solder bond fatigue models derived for electronics packaging applications can be applied to both standard and emerging PV interconnect designs. This expertise cannot be directly translated to PV however, as target PV module lifetimes are significantly longer than most electronics and the modules must withstand the natural climate wherever they are deployed. Verification of analytical reliability models is then an additional challenge, due to model size, test time, and climate variability. Furthermore, unconventional materials, such as low-temperature solders, are now being integrated into PV designs, for which appropriate material models must be selected and material parameters derived. In this paper, the current state of PV interconnect research is explored, with an emphasis on the experimental and simulation approaches and models being used for this work. Recent results for standard module architectures as well as emerging interconnect schemes are discussed.

scholarly journals Mobile-PolypNet : Light-weight Colon Polyp Segmentation Network for Low Resources Settings

2021 ◽  
Author(s):  
Ranit Karmakar ◽  
Saeid Nooshabadi
Keyword(s):  
Deep Learning ◽  
State Of The Art ◽  
Colorectal Polyp ◽  
P Value ◽  
Colon Polyps ◽  
Current State ◽  
Model Size ◽  
Ablation Study ◽  
Small Clump ◽  
Deep Learning Model

Abstract Colon polyps, small clump of cells on the lining of the colon can lead to Colorectal cancer (CRC), one of the leading types of cancer globally. Hence, early detection of these polyps is crucial in the prevention of CRC. This paper proposes a lightweight deep learning model for colorectal polyp segmentation that achieved state-of-the-art accuracy while significantly reducing the model size and complexity. The proposed deep learning autoencoder model employs a set of state-of-the-art architectural blocks and optimization objective functions to achieve the desired efficiency. The model is trained and tested on five publicly available colorectal polyp segmentation datasets (CVC-ClinicDB, CVC-ColonDB, EndoScene, Kvasir, and ETIS). We also performed ablation testing on the model to test various aspects of the autoencoder architecture. We performed the model evaluation using most of the common image segmentation metrics. The backbone model achieved a dice score of 0.935 on the Kvasir dataset and 0.945 on the CVC-ClinicDB dataset improving the accuracy by 4.12% and 5.12% respectively over the current state-of-the-art network, while using 88 times fewer parameters, 40 times less storage space, and being computationally 17 times more efficient. Our ablation study showed that the addition of ConvSkip in the autoencoder slightly improves the model’s performance but it was not significant (p-value=0.815).

scholarly journals Flow Inside the Sidewall Gaps of Hydraulic Machines: A Review

Energies ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 6617
Author(s):  
Lucie Zemanová ◽  
Pavel Rudolf
Keyword(s):  
Secondary Flow ◽  
Operating Characteristics ◽  
Axial Thrust ◽  
Numerical Studies ◽  
Current State ◽  
Hydraulic Machines ◽  
Disk Friction ◽  
Low Specific Speed ◽  
Overall Performance ◽  
Physical Phenomena

The paper critically reviews the current state of the art in flow inside sidewall gaps of hydraulic pumps and turbines. It describes the consequences of the presence of this type of flow in turbomachinery and then relates it to other physical phenomena that determine the behavior, operating characteristics, and overall performance of the machine. Despite the small dimensions of the rotor-stator spaces, the flow in these regions can significantly affect the overall flow field and, consequently, efficiency. The circulation of the fluid inside the gaps and secondary flow that is caused by rotating elements influences the disk friction losses, which is of great importance, especially in the case of low specific speed pumps and turbines. The flow pattern affects the pressure distribution inside a machine and, thus, generates axial thrust. The presence of secondary flow also significantly changes the rotordynamics and can bring about undesirable vibrations and acoustics issues. This article aims to review and summarize the studies that were conducted on the mentioned phenomena. Experimental and numerical studies are both taken into consideration. It proposes some requirements for prospective research in order to fill current gaps in the literature and reveals the upcoming challenges in the design of hydraulic machines.

scholarly journals Current state and prospects of detectors in the terahertz range. Part 2. Heterodyne detection of terahertz radiation

2021 ◽  
Vol 9 (6) ◽  
pp. 499-512
Author(s):  
Nikolay Kulchitsky ◽  
Arkadii Naumov ◽  
Vadim Startsev ◽  
Mikhail Dem’yanenko
Keyword(s):  
Terahertz Radiation ◽  
Recent Progress ◽  
Direct Detection ◽  
Radiation Detectors ◽  
Terahertz Range ◽  
Heterodyne Detection ◽  
Advantages And Disadvantages ◽  
Current State ◽  
Range Part ◽  
Physical Phenomena

The paper discusses the problems associated with the development of technology for terahertz radiation detectors. The main physical phenomena and recent progress in various methods of detecting terahertz radiation (direct detection and heterodyne detection) are considered. Advantages and disadvantages of direct detection sensors and sensors with heterodyne detection are discussed. In part 1, a number of features of direct detection are considered and some types of terahertz direct detection detectors are described. Part 2 will describe heterodyne detection and continue to describe some types of modern photonic terahertz receivers.

scholarly journals Physical Phenomena in Nuclear Thermal Hydraulics and Current Status

2021 ◽  
Vol 65 (1) ◽  
pp. 1-11
Author(s):  
F. D’Auria ◽  
N. Aksan ◽  
H. Glaeser
Keyword(s):  
Current Status ◽  
Thermal Hydraulics ◽  
Two Phase ◽  
Energy Agency ◽  
Pressurized Water ◽  
Current State ◽  
Integral Effect ◽  
Water Reactors ◽  
Physical Phenomena ◽  
Effect Test

116 nuclear Thermal-Hydraulic Phenomena T-HP are identified in the present paper, following documents issued during the last three decades by the Committee on the Safety of Nuclear Installations of Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD/NEA/CSNI) and by the International Atomic Energy Agency (IAEA). The derived T-HP list includes consideration of experiments performed in Separate Effect Test (SET) and Integral Effect Test (IET) facilities relevant to reactor coolant system and containment of Water Cooled Nuclear Reactors (WCNR). We consider a dozen WCNR types: Pressurized Water Reactors (PWR), Boiling Water Reactors (BWR), Russian reactors (VVER-440, VVER-1000 and RBMK), pressure tube heavy water reactors by Canada (CANDU) and India (PHWR) and so-called ‘advanced’ reactors (e.g. AP-1000 and APR-1400 designed in US and Korea, respectively). We envisage a variety of applications for the T-HP list. Four of the phenomena are helpful to characterize the current state of art in nuclear thermal-hydraulics: Counter Current Flow Limitation (CCFL), Critical Heat Flux (CHF), reflood and Two-Phase Critical Flow (TPCF). Furthermore, the T-HP identification contributes to addressing the scaling issue, performing uncertainty evaluations, developing constitutive equations and ‘special models’ in codes and prioritizing the research.

High-Performance Packaging of Power Electronics

MRS Bulletin ◽  
2003 ◽  
Vol 28 (1) ◽  
pp. 41-50 ◽  
Author(s):  
M. C. Shaw
Keyword(s):  
Heat Transfer ◽  
Solid State ◽  
Power Electronics ◽  
High Performance ◽  
Materials Science ◽  
State Of The Art ◽  
State Power ◽  
Electronics Packaging ◽  
Current State ◽  
Interdisciplinary Process

AbstractPackaging of solid-state power electronics is a highly interdisciplinary process requiring knowledge of electronics, heat transfer, mechanics, and materials science. Consequently, there are numerous opportunities for innovations at the interfaces of these complementary fields. This article offers a perspective of the current state of the art and identifies six specific areas for materials-based research in power electronics packaging. The emphasis is on identifying the underlying physical relationships that link the performance of the power electronics system to the microstructure and architectural arrangement of the constituents.

scholarly journals PixelBNN: Augmenting the PixelCNN with Batch Normalization and the Presentation of a Fast Architecture for Retinal Vessel Segmentation

2019 ◽  
Vol 5 (2) ◽  
pp. 26 ◽  
Author(s):  
Henry Leopold ◽  
Jeff Orchard ◽  
John Zelek ◽  
Vasudevan Lakshminarayanan
Keyword(s):  
State Of The Art ◽  
Retinal Vessel ◽  
Vessel Segmentation ◽  
Test Time ◽  
Fundus Images ◽  
Current State ◽  
Trade Offs ◽  
Disease Condition ◽  
Efficiency Performance ◽  
Retinal Vessel Segmentation

Analysis of retinal fundus images is essential for eye-care physicians in the diagnosis, care and treatment of patients. Accurate fundus and/or retinal vessel maps give rise to longitudinal studies able to utilize multimedia image registration and disease/condition status measurements, as well as applications in surgery preparation and biometrics. The segmentation of retinal morphology has numerous applications in assessing ophthalmologic and cardiovascular disease pathologies. Computer-aided segmentation of the vasculature has proven to be a challenge, mainly due to inconsistencies such as noise and variations in hue and brightness that can greatly reduce the quality of fundus images. The goal of this work is to collate different key performance indicators (KPIs) and state-of-the-art methods applied to this task, frame computational efficiency–performance trade-offs under varying degrees of information loss using common datasets, and introduce PixelBNN, a highly efficient deep method for automating the segmentation of fundus morphologies. The model was trained, tested and cross tested on the DRIVE, STARE and CHASE_DB1 retinal vessel segmentation datasets. Performance was evaluated using G-mean, Mathews Correlation Coefficient and F1-score, with the main success measure being computation speed. The network was 8.5× faster than the current state-of-the-art at test time and performed comparatively well, considering a 5× to 19× reduction in information from resizing images during preprocessing.

Software Reliability Test Methods Based on Component Composition and Markov Process

2013 ◽  
Vol 660 ◽  
pp. 169-173 ◽  
Author(s):  
Zhi Jie Gao ◽  
Fu Chun Sun ◽  
Ling Lu
Keyword(s):  
Software Reliability ◽  
Flight Control ◽  
Component Composition ◽  
Test Methods ◽  
Test Time ◽  
Software Systems ◽  
Test Results ◽  
Software Module ◽  
Reliability Models ◽  
Saturation Effects

With the continuous improvement of the software quality requirements, more and more attentions are paid to the reliability of software systems. Most of the existing reliability models rely on the cumulative test time to characterize the reliability improvement, while ignoring the saturation effects and software module failure characteristic differences exist, making the test results to low confidence. In this paper, Markov description methods are utilized in reliability calculating process to improve the fictitious-excellence problem in current testing models. Finally, the method is applied to a flight control system software reliability testing. The results demonstrate the effectiveness of the method.

scholarly journals Current state and prospects of detectors in the terahertz range Part 1. Direct detection of terahertz radiation

2021 ◽  
Vol 9 (1) ◽  
pp. 68-85
Keyword(s):  
Terahertz Radiation ◽  
Direct Detection ◽  
Radiation Detectors ◽  
Terahertz Range ◽  
Heterodyne Detection ◽  
Advantages And Disadvantages ◽  
Current State ◽  
Range Part ◽  
Physical Phenomena

The paper discusses the problems associated with the development of technology for terahertz radiation detectors. The main physical phenomena and recent pro-gress in various methods of detecting terahertz radiation (direct detection and het-erodyne detection) are considered. Advantages and disadvantages of direct detec-tion sensors and sensors with heterodyne detection are discussed. In part 1, a number of features of direct detection are considered and some types of terahertz direct detection detectors are described. Part 2 will describe heterodyne detection and continue to describe some types of modern photonic terahertz receivers.

scholarly journals Classification and analysis of measuring transducers of intensity (induction) of alternating magnetic fields

2021 ◽  
pp. 82-93
Author(s):  
Yurii Bobkov
Keyword(s):  
Magnetic Fields ◽  
Magnetic Measurements ◽  
Advantages And Disadvantages ◽  
Current State ◽  
Primary Measuring ◽  
Wide Range ◽  
The Right ◽  
Physical Phenomena ◽  
Alternating Magnetic Fields

The current state of technology is characterized by the mass use of electricity, the use of various electrical, electronic and radio devices. This causes expansion of magnetic measurements and the need to develop new highly sensitive measuring equipment for a wide range of frequencies. One of its main elements, that largely determines the accuracy, frequency and dynamic ranges, are the primary measuring sensors of strength (induction) of alternating magnetic fields. Many works have been devoted to the analysis and development of various sensors of strength (induction) of magnetic fields. At the same time, it can be noted the lack of a systematic approach to the measurement of alternating magnetic fields. The problem of the general classification of methods of measurement of alternating magnetic fields and, accordingly, primary measuring sensors of strength (induction) of alternating magnetic fields is not solved. In most cases, separate issues of measuring alternating magnetic fields and certain types of sensors are considered. That does not allow obtaining a holistic picture in this area and make the right choice of direction for solving assigned tasks. The comprehensive analysis of methods of measuring alternating magnetic fields was carried out in this work. Based on it, the classification of primary measuring sensors of strength (induction) of alternating magnetic fields, on the physical principles of transformation was proposed. Accordingly, the available measuring sensors of alternating magnetic fields following to the group of used physical phenomena can be divided into: magnetomechanical, induction, galvanomagnetic, quantum, magneto-optical and photomagnetic. Depending on the characteristics of each of these phenomena, separate measurement methods and types of measuring sensors were highlighted. The current state of development of each of the types of measuring sensors of strength of alternating magnetic fields was analyzed, their advantages and disadvantages were determined, the limits of dynamic and frequency ranges, the maximum values of errors were outlined. The obtained results allow to significantly simplify and reduce the time of choosing the necessary method of strength (induction) of alternating magnetic fields measuring and to choose the necessary type of measuring sensor to effectively solve the tasks.

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