scholarly journals Strengthening the masonry bridges with use of corrugated steel plates

2016 ◽  
Vol 2016 (1) ◽  
pp. 36-42 ◽  
Author(s):  
Czesław Machelski
Keyword(s):  
Small Area ◽  
High Efficiency ◽  
Steel Structures ◽  
Steel Plates ◽  
Long Time ◽  
Masonry Vaults ◽  
Construction Works

The following work presents the problem of old arched bridges, built a long time ago as masonry constructions and their revitalization. Nowadays this kind of railway structures is very popular and extensively used in Europe. Moreover, in Poland there is a significant number of them. This work considers the possibility of strengthening these objects with using the corrugated steel plates as the material which is already being used in soil-steel structures. The usage of steel coatings is very con-venient while providing any construction works as they are taking place underneath the arch. This is not causing any restrictions of movements on the bridge as only a small area under the bridge is oc-cupied. According to different coatings geometry, this kind of technology is being presented based on already existing objects as the examples. The following study proves high efficiency of strength-ening the masonry vaults with the usage of corrugated steel plates.

Performance of thin-walled steel structures by longitudinally and transeversely profiled steel plates

2007 ◽  
Author(s):  
Takuji Kumano ◽  
Kunimoto Sugiura ◽  
Takashi Yamaguchi ◽  
Eiichi Watanabe ◽  
Yasuo Suzuki
Keyword(s):  
Steel Structures ◽  
Steel Plates ◽  
Thin Walled

scholarly journals Novel semi-analytical optoelectronic modeling based on homogenization theory for realistic plasmonic polymer solar cells

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zahra Arefinia ◽  
Dip Prakash Samajdar
Keyword(s):  
Solar Cells ◽  
Active Layer ◽  
Analytical Modeling ◽  
High Efficiency ◽  
Polymer Solar Cells ◽  
Scattered Light ◽  
Homogenization Theory ◽  
Computational Time ◽  
Coupled Equations ◽  
Long Time

AbstractNumerical-based simulations of plasmonic polymer solar cells (PSCs) incorporating a disordered array of non-uniform sized plasmonic nanoparticles (NPs) impose a prohibitively long-time and complex computational demand. To surmount this limitation, we present a novel semi-analytical modeling, which dramatically reduces computational time and resource consumption and yet is acceptably accurate. For this purpose, the optical modeling of active layer-incorporated plasmonic metal NPs, which is described by a homogenization theory based on a modified Maxwell–Garnett-Mie theory, is inputted in the electrical modeling based on the coupled equations of Poisson, continuity, and drift–diffusion. Besides, our modeling considers the effects of absorption in the non-active layers, interference induced by electrodes, and scattered light escaping from the PSC. The modeling results satisfactorily reproduce a series of experimental data for photovoltaic parameters of plasmonic PSCs, demonstrating the validity of our modeling approach. According to this, we implement the semi-analytical modeling to propose a new high-efficiency plasmonic PSC based on the PM6:Y6 PSC, having the highest reported power conversion efficiency (PCE) to date. The results show that the incorporation of plasmonic NPs into PM6:Y6 active layer leads to the PCE over 18%.

scholarly journals On Performance of Sparse Fast Fourier Transform Algorithms Using the Aliasing Filter

Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1117
Author(s):  
Bin Li ◽  
Zhikang Jiang ◽  
Jie Chen
Keyword(s):  
Fourier Transform ◽  
Fast Fourier Transform ◽  
High Efficiency ◽  
Theory And Practice ◽  
Long Time ◽  
And Performance ◽  
Binary Tree Search ◽  
The One ◽  
Sparse Fast Fourier Transform ◽  
L1 And L2

Computing the sparse fast Fourier transform (sFFT) has emerged as a critical topic for a long time because of its high efficiency and wide practicability. More than twenty different sFFT algorithms compute discrete Fourier transform (DFT) by their unique methods so far. In order to use them properly, the urgent topic of great concern is how to analyze and evaluate the performance of these algorithms in theory and practice. This paper mainly discusses the technology and performance of sFFT algorithms using the aliasing filter. In the first part, the paper introduces the three frameworks: the one-shot framework based on the compressed sensing (CS) solver, the peeling framework based on the bipartite graph and the iterative framework based on the binary tree search. Then, we obtain the conclusion of the performance of six corresponding algorithms: the sFFT-DT1.0, sFFT-DT2.0, sFFT-DT3.0, FFAST, R-FFAST, and DSFFT algorithms in theory. In the second part, we make two categories of experiments for computing the signals of different SNRs, different lengths, and different sparsities by a standard testing platform and record the run time, the percentage of the signal sampled, and the L0, L1, and L2 errors both in the exactly sparse case and the general sparse case. The results of these performance analyses are our guide to optimize these algorithms and use them selectively.

scholarly journals Investigations on arc brazing for galvanized heavy steel plates in steel and shipbuilding

2021 ◽  
Author(s):  
Philipp Andreazza ◽  
Andreas Gericke ◽  
Knuth-Michael Henkel
Keyword(s):  
Low Cost ◽  
Thin Sheet ◽  
Steel Structures ◽  
Tensile Tests ◽  
Fatigue Tests ◽  
Steel Plates ◽  
Galvanized Steel ◽  
Filler Materials ◽  
Static Tensile ◽  
Brazed Joints

AbstractArc brazing with low-melting copper-based filler materials, which has long been established and standardized in the thin sheet sector, offers numerous advantages in the processing of predominantly electrolytically galvanized steel structures. In steel and shipbuilding, on the other hand, equipment parts made of thick steel sheets are hot-dip galvanized at low cost and with good corrosion-inhibiting properties. Quality welding of such constructions is not possible without special precautions such as removing the zinc layer and subsequent recoating. With regard to greater plate thicknesses, arc brazing was analyzed in these investigations as an alternative joining method with regard to its suitability for practical use. Within the scope of the investigations, CuSi3Mn, CuMn12Ni2, and four different aluminum bronzes were examined on different sheet surface conditions with regard to the geometrical and production parameters. This was carried out by build-up and connection brazing, executed as butt and cross joints. Quasi-static tensile tests and fatigue tests were used to assess the strength behavior. In addition, metallographic analyses are carried out as well as hardness tests. The suitability for multi-layer brazing and the tendency to distortion were also investigated, as well as the behavior of arc brazed joints under corrosive conditions.

A New Prediction Model on the Luminance of OLEDs Subjected to Different Reverse Biases for Alleviating Degradation in AMOLED Displays

2014 ◽  
Author(s):  
Paul C.-P. Chao ◽  
Yen-Ping Hsu ◽  
Yung-Hua Kao ◽  
Kuei-Yu Lee
Keyword(s):  
Reverse Bias ◽  
High Efficiency ◽  
Life Time ◽  
Density Currents ◽  
High Brightness ◽  
Light Emitting ◽  
Wide Viewing Angle ◽  
Time Operation ◽  
Long Time ◽  
History Of

Organic light-emitting diodes (OLEDs) have drawn much attention in areas of displays and varied illumination devices due to multiple advantages, such as high brightness, high efficiency, wide viewing angle, and simple structure. However, the long-time degradation of OLED emission is a serious drawback. This degradation was investigated by past works, which pointed out that the degradation was induced by high-density currents through OLED component under the long-time operation [1][2]. Proposed by a past work [3], different reverse biases was imposed on OLED components in display frames to alleviate the long-time degradation on OLEDs. Most recently, along with the reverse bias, new pixel circuits [4][5] for AMOLED displays are designed to alleviate OLED degradation, thus successfully extending OLED life time. However, since emission luminances in different frame times during AMOLED displaying differs significantly for displaying varied images, the OLED degradation evolves in a highly unpredictable fashion. In this study, based on valid theories, the voltage across the OLED is first used as indicator for OLED degradation. Then the relation between the level of OLED degradation, in terms of OLED’s cross voltage, and the history of imposing reverse biases are precisely modeled. With the model, the degradation of the OLED under reverse bias to extend lifetime can be successfully predicted. Based on this model, engineers can then optimize the applied reverse bias on OLEDs to maximize the OLED lifetime for varied display requirement.

scholarly journals Development of COVID-19 vaccines utilizing gene therapy technology

2021 ◽  
Author(s):  
Hironori Nakagami
Keyword(s):  
Viral Vectors ◽  
High Efficiency ◽  
Genetic Disorders ◽  
Rapid Development ◽  
Adenovirus Vector ◽  
Phase 3 ◽  
Double Blind ◽  
Time Period ◽  
Short Period ◽  
Long Time

Abstract There is currently an outbreak of respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Coronavirus disease 2019 (COVID-19) is caused by infection with SARS-CoV-2. Individuals with COVID-19 have symptoms that are usually asymptomatic or mild in most initial cases. However, in some cases, moderate and severe symptoms have been observed with pneumonia. Many companies are developing COVID-19 vaccine candidates using different technologies that are classified into four groups (intact target viruses, proteins, viral vectors and nucleic acids). For rapid development, RNA vaccines and adenovirus vector vaccines have been urgently approved, and their injection has already started across the world. These types of vaccine technologies have been developed over more than 20 years using translational research for use against cancer or diseases caused by genetic disorders but the COVID-19 vaccines are the first licensed drugs to prevent infectious diseases using RNA vaccine technology. Although these vaccines are highly effective in preventing COVID-19 for a short period, safety and efficiency evaluations should be continuously monitored over a long time period. As the time of writing, more than 10 projects are now in phase 3 to evaluate the prevention of infection in double-blind studies. Hopefully, several projects may be approved to ensure high-efficiency and safe vaccines.

scholarly journals Electromechanical Modeling and Simulation of Piezoelectric Vibration based Energy Harvester Interfaced with MPPT based Electrical Circuit using Matlab Simulink

2019 ◽  
Vol 8 (2S11) ◽  
pp. 36-40
Keyword(s):  
Energy Harvester ◽  
High Efficiency ◽  
Electrical Circuit ◽  
Vibration Energy Harvester ◽  
Matlab Simulink ◽  
Electromechanical Model ◽  
Wind Vibration ◽  
Long Time ◽  
Piezoelectric Vibration ◽  
High Output

Wind vibration based energy harvester using piezoelectric material has been of great concern to researchers for a long time for low power generation and applications. In this paper, wind generated vibrations are used to develop electromechanical model of piezoelectric vibration energy harvester to generate electrical output using MATLAB simulink and comparision has been drawn between an electromechanical model of piezoelectric harvester interfaced with P&O MPPT based electrical model and without it. It has been found that overall model with MPPT provides high output with high efficiency

A Study on the Efficiency Improvement of Dye-Sensitized Solar Cell (DSSC) by Repeated Dye Coating

2015 ◽  
Vol 15 (10) ◽  
pp. 7706-7710
Author(s):  
Young Ho Seo ◽  
Eun Chang Choi ◽  
Byungyou Hong
Keyword(s):  
Solar Cell ◽  
High Efficiency ◽  
Dye Adsorption ◽  
Working Environment ◽  
Dye Sensitized Solar Cell ◽  
Coating Process ◽  
Cell Efficiency ◽  
Dye Sensitized ◽  
Long Time ◽  
Low Efficiency

Dye-sensitized solar cell (DSSC) is being extensively investigated as the next generation energy source. Despite of the attractive features like simple fabrication process and its economic efficiency, there are some problems such as low efficiency, long fabrication time and low long-term stability. Conventionally, the dye adsorption on TiO2 photo-electrode film needs long time in the solvent with low concentration of dye to get the high efficiency. In this work, the dye coating process was considerably shortened, albeit plenty of dye was used comparing with the conventional way. Our needs were met for the best result in our working environment and the relevant conditions to our work were obtained, which were the coating temperature of 70 °C, the dye concentration of 10 mM and the coating time of 3 min. And this coating process was successively repeated several times to maximize the dye adsorption and to improve the cell efficiency. Therefore, the efficiency increased by 13% in the proper condition.

Multi-Frequency Heterodyne Phase Shift Technology in 3-D Measurement

2013 ◽  
Vol 774-776 ◽  
pp. 1582-1585 ◽  
Author(s):  
Le Wang ◽  
Lei Song ◽  
Li Jun Zhong ◽  
Peng Xin ◽  
Shuai Li ◽  
...  
Keyword(s):  
Phase Shift ◽  
Small Area ◽  
Fringe Pattern ◽  
Measurement Accuracy ◽  
High Efficiency ◽  
Median Filter ◽  
Distinct Advantage ◽  
Accuracy Measurement ◽  
Fringe Patterns ◽  
Spin Filtering

According to the characteristics of the fringe patterns noise, came up with a small area spin filtering noise cancellation algorithm based on parallel marker technology. It means that preprocess the fringe pattern before spin filtering, then did a median filter and calculated the stripe direction, finally used the extract the fringe direction to spin filtering of the original image. The algorithm can marked several targets in scanning process at the same time. So it has a high efficiency. The algorithm can be used in the multi-frequency heterodyne phase shift technology .And we can use the technology to complete the measurement of complex surfaces. Experimental results show that the method has a distinct advantage in measurement accuracy, measurement speed, and noise immunity.

High efficiency, small-area bends in low index contrast waveguides

2003 ◽  
Author(s):  
L. Li ◽  
G. P. Nordin ◽  
J. Jiang ◽  
J. M. English
Keyword(s):  
Small Area ◽  
High Efficiency ◽  
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