scholarly journals Piezo drive tunable optic filter

2021 ◽  
Author(s):  
Wen Zu
Keyword(s):  
High Performance ◽  
Tuning Range ◽  
Fiber Optic ◽  
High Reliability ◽  
Axial Strain ◽  
Reaction Force ◽  
Fine Tuning ◽  
Element Analysis ◽  
Compensation Design

Tunable fiber optic filter has extensive applications in telecommunications, spectroscopy, and fiber optic sensing. Many research attempts have been devoted to develop a filter with a wide tuning range, a fast tuning speed, a fine tuning resolution, and high reliability. Despite of the progress made so far, a tunable fiber optic filter that combines all these qualities is still a subject of intensive research. This thesis describes the design, fabrication and test results of a high performance tunable fiber optic filter. The filter is piezo-driven using a flexural hinge structure for displacement magnification and an axial strain of a fiber Bragg grating. Finite element analysis was used to design the mechanical structure to achieve the required displacement magnification and reaction force for grating compression. A passive thermal compensation design was implemented with two spacers of different coefficients of thermal expansion to compensate the thermal-induced wavelength drift. A feedback control system with a linear variable differential transformer was employed to control the displacement and to achieve the designed tuning accuracy. A tuning range of 13.7 nm, a maximum closed loop switching time of 17.3 ms, and a wavelength drift of 1.4 pm/C were achieved. The flexural-hinge structure, that offers noise-free motion, no need of lubricants and no wear, ensures its long-term reliability.

scholarly journals Piezo drive tunable optic filter

2021 ◽  
Author(s):  
Wen Zu
Keyword(s):  
High Performance ◽  
Tuning Range ◽  
Fiber Optic ◽  
High Reliability ◽  
Axial Strain ◽  
Reaction Force ◽  
Fine Tuning ◽  
Element Analysis ◽  
Compensation Design

Tunable fiber optic filter has extensive applications in telecommunications, spectroscopy, and fiber optic sensing. Many research attempts have been devoted to develop a filter with a wide tuning range, a fast tuning speed, a fine tuning resolution, and high reliability. Despite of the progress made so far, a tunable fiber optic filter that combines all these qualities is still a subject of intensive research. This thesis describes the design, fabrication and test results of a high performance tunable fiber optic filter. The filter is piezo-driven using a flexural hinge structure for displacement magnification and an axial strain of a fiber Bragg grating. Finite element analysis was used to design the mechanical structure to achieve the required displacement magnification and reaction force for grating compression. A passive thermal compensation design was implemented with two spacers of different coefficients of thermal expansion to compensate the thermal-induced wavelength drift. A feedback control system with a linear variable differential transformer was employed to control the displacement and to achieve the designed tuning accuracy. A tuning range of 13.7 nm, a maximum closed loop switching time of 17.3 ms, and a wavelength drift of 1.4 pm/C were achieved. The flexural-hinge structure, that offers noise-free motion, no need of lubricants and no wear, ensures its long-term reliability.

Fiber optic gyros in a high-performance, high-reliability inertial reference unit for commercial satellites

2012 ◽  
Author(s):  
S. Sanders ◽  
A. Taranta ◽  
S. Mosor ◽  
M. Alden ◽  
L. Hendry ◽  
...  
Keyword(s):  
High Performance ◽  
Fiber Optic ◽  
High Reliability

1200V SiC Trench-MOSFET Optimized for High Reliability and High Performance

2017 ◽  
Vol 897 ◽  
pp. 489-492 ◽  
Author(s):  
Dethard Peters ◽  
Thomas Aichinger ◽  
Thomas Basler ◽  
Wolfgang Bergner ◽  
Daniel Kueck ◽  
...  
Keyword(s):  
Detailed Analysis ◽  
Gate Voltage ◽  
High Performance ◽  
High Reliability ◽  
Dynamic Performance ◽  
Life Time ◽  
Gate Oxide ◽  
Voltage Range ◽  
Failure Evolution

A detailed analysis of the typical static and dynamic performance of the new developed Infineon 1200V CoolSiCTM MOSFET is shown which is designed for an on-resistance of 45 mΩ. In order to be compatible to various standard gate drivers the gate voltage range is designed for-5 V in off-state and +15 V in on-state. Long term gate oxide life time tests reveal that the extrinsic failure evolution follows the linear E-model which allows a confident prediction of the failure rate within the life time of the device of 0.2 ppm in 20 years under specified use condition.

scholarly journals Biomechanical Evaluation of a Tooth Restored with High Performance Polymer PEKK Post-Core System: A 3D Finite Element Analysis

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Ki-Sun Lee ◽  
Joo-Hee Shin ◽  
Jong-Eun Kim ◽  
Jee-Hwan Kim ◽  
Won-Chang Lee ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Cyclic Loading ◽  
High Performance ◽  
Core Material ◽  
Element Analysis ◽  
Core System ◽  
High Performance Polymer ◽  
Core Materials

The aim of this study was to evaluate the biomechanical behavior and long-term safety of high performance polymer PEKK as an intraradicular dental post-core material through comparative finite element analysis (FEA) with other conventional post-core materials. A 3D FEA model of a maxillary central incisor was constructed. A cyclic loading force of 50 N was applied at an angle of 45° to the longitudinal axis of the tooth at the palatal surface of the crown. For comparison with traditionally used post-core materials, three materials (gold, fiberglass, and PEKK) were simulated to determine their post-core properties. PEKK, with a lower elastic modulus than root dentin, showed comparably high failure resistance and a more favorable stress distribution than conventional post-core material. However, the PEKK post-core system showed a higher probability of debonding and crown failure under long-term cyclic loading than the metal or fiberglass post-core systems.

scholarly journals Cabled Ocean Observatory Systems

2004 ◽  
Vol 38 (2) ◽  
pp. 30-43 ◽  
Author(s):  
Alan D. Chave ◽  
Gary Waterworth ◽  
Andrew R. Maffei ◽  
Gene Massion
Keyword(s):  
Fiber Optic ◽  
High Reliability ◽  
Power Grid ◽  
System Engineering ◽  
Power Cable ◽  
Future Studies ◽  
Control Instrument ◽  
Engineering Environment ◽  
And Control

Future studies of episodic processes in the ocean and earth will require new tools to complement traditional, ship-based, expeditionary science. This will be enabled through the construction of innovative facilities called ocean observatories which provide unprecedented amounts of power and two-way bandwidth to access and control instrument networks in the oceans. The most capable ocean observatories are designed around a submarine fiber optic/power cable connecting one or more seafloor science nodes to the terrestrial power grid and communications backhaul. This paper defines the top level requirements that drive cabled observatory design and the system engineering environment within which a scientifically-capable infrastructure can be implemented. Commercial high reliability submarine telecommunication technologies which will be crucial in the design of long term cabled observatories are then reviewed. The top level architecture of a generic cabled observatory, describing the main subsystems comprising the whole and defining technological approaches to their engineering, is then described, along with some example design choices and tradeoff studies

Finite Element Analysis and Long-Term Monitoring of a Highway Overpass Bridge with Newly Constructed Link Slabs and Modified Bearings

2021 ◽  
pp. 036119812110611
Author(s):  
Yifan Zhu ◽  
Kuangyuan Hou ◽  
Chung C. Fu ◽  
Naiyi Li ◽  
Ruel E. Sabellano
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Highway Bridges ◽  
Pilot Project ◽  
Functional Condition ◽  
Element Analysis ◽  
One Year ◽  
The One ◽  
Replacement Design

Joint failure, which causes leakage in bridge decks as well as deterioration in girders and substructures, is one of the most common concerns in highway bridges. Therefore, link slabs have been considered as a preventive maintenance method in eliminating these joints. This paper presents a pilot project that constructed the link slab system in Maryland, U.S., with modified bearings to improve its durability and reduce maintenance costs. Compared with the traditional bearing replacement design for the link slab systems, this project proposes a more economical method by removing the anchor bolts and restricting sliding plates of the fixed bearings at both abutments to match the designed boundary conditions while avoiding the high cost of jacking girders and replacing bearings. Furthermore, numerical analysis and structural health monitoring were conducted and validated to investigate the effectiveness of the link slab design with various high performance concrete materials. After the one-year monitoring period, the link slab system is verified to be in fully functional condition and the bearing modification design is verified to be effective.

Adapting the high performance organization framework to the Thai context

2014 ◽  
Vol 18 (2) ◽  
pp. 28-38 ◽  
Author(s):  
Andre A. de Waal ◽  
Robert Goedegebuure ◽  
Chiraprapha Tan Akaraborworn
Keyword(s):  
High Performance ◽  
High Reliability ◽  
Western World ◽  
Orientation Factor ◽  
Content Type ◽  
Business Context ◽  
High Performance Organization ◽  
Thai Organizations ◽  
Thai Business

Purpose – The purpose of this study is evaluate whether the high performance organization (HPO) framework can satisfy the recent urgent request of Thai business leaders to create a unique organization which is better able to deal with unpredictable circumstances and increased competition. To establish the suitability of the HPO Framework it first has to be made sure that this framework is applicable to the Thai business context as previous research has shown that management techniques originating from the Western world cannot be indiscriminately transferred into non-Western contexts. Design/methodology/approach – During several workshops and seminars in Bangkok, participants were asked to complete the HPO questionnaire. The collected data were analyzed using a second-order confirmatory factor analysis to evaluate whether the data on the 35 items in the HPO framework group into the five independent factors: continuous improvement, openness and action orientation, management quality, workforce quality and long-term orientation. Findings – The data yielded, with a high reliability, four of the five HPO factors as present in the original HPO framework. The dropped items were either confounded with other factors or items that may be another dimension in the data or a sub-dimension of other factors. The long-term orientation factor was dropped, as the accompanying items did not unidimensionally measure this construct. This did not mean that long-term orientation (LTO) is not relevant in the Thai context; there simply were no items included that measured LTO properly in the Thai context. Research implications – The HPO framework proved to be a validated and valuable technique for Thai organizations to improve in a sustainable way. Further research should focus on testing the HPO framework in practice by implementing the framework in Thai organizations and then tracking the performance of these organizations over time. In this way, it can be evaluated if the advantages experienced by organizations while applying the HPO framework can also be enjoyed by Thai organizations. Originality/value – This is the first research into the validity of the HPO framework in the specific Thai context.

A High Performance and Low Bandwidth Multi-Standard Motion Compensation Design for HD Video Decoder

2010 ◽  
Vol E93-C (3) ◽  
pp. 253-260 ◽  
Author(s):  
Xianmin CHEN ◽  
Peilin LIU ◽  
Dajiang ZHOU ◽  
Jiayi ZHU ◽  
Xingguang PAN ◽  
...  
Keyword(s):  
Motion Compensation ◽  
High Performance ◽  
Video Decoder ◽  
Compensation Design

Parallel Computing for Tire Simulations

2011 ◽  
Vol 39 (3) ◽  
pp. 193-209 ◽  
Author(s):  
H. Surendranath ◽  
M. Dunbar
Keyword(s):  
High Performance ◽  
Effective Means ◽  
Cost Effective ◽  
Turnaround Time ◽  
Careful Consideration ◽  
Rolling Contact ◽  
Element Analysis ◽  
Parallel Solvers ◽  
Design Changes ◽  
Highly Nonlinear

Abstract Over the last few decades, finite element analysis has become an integral part of the overall tire design process. Engineers need to perform a number of different simulations to evaluate new designs and study the effect of proposed design changes. However, tires pose formidable simulation challenges due to the presence of highly nonlinear rubber compounds, embedded reinforcements, complex tread geometries, rolling contact, and large deformations. Accurate simulation requires careful consideration of these factors, resulting in the extensive turnaround time, often times prolonging the design cycle. Therefore, it is extremely critical to explore means to reduce the turnaround time while producing reliable results. Compute clusters have recently become a cost effective means to perform high performance computing (HPC). Distributed memory parallel solvers designed to take advantage of compute clusters have become increasingly popular. In this paper, we examine the use of HPC for various tire simulations and demonstrate how it can significantly reduce simulation turnaround time. Abaqus/Standard is used for routine tire simulations like footprint and steady state rolling. Abaqus/Explicit is used for transient rolling and hydroplaning simulations. The run times and scaling data corresponding to models of various sizes and complexity are presented.

Efficient Co-Harvesting of Solar Energy and Low-Grade Heat by Molecular Photoswitches for High Energy Density, Long-Term Stable Solar Thermal Battery

2019 ◽  
Author(s):  
Zhao-Yang Zhang ◽  
Tao LI
Keyword(s):  
Energy Density ◽  
Solar Energy ◽  
High Performance ◽  
High Energy ◽  
Solar Thermal ◽  
High Energy Density ◽  
Low Grade ◽  
Thermal Battery ◽  
Low Grade Heat

Solar energy and ambient heat are two inexhaustible energy sources for addressing the global challenge of energy and sustainability. Solar thermal battery based on molecular switches that can store solar energy and release it as heat has recently attracted great interest, but its development is severely limited by both low energy density and short storage stability. On the other hand, the efficient recovery and upgrading of low-grade heat, especially that of the ambient heat, has been a great challenge. Here we report that solar energy and ambient heat can be simultaneously harvested and stored, which is enabled by room-temperature photochemical crystal-to-liquid transitions of small-molecule photoswitches. The two forms of energy are released together to produce high-temperature heat during the reverse photochemical phase change. This strategy, combined with molecular design, provides high energy density of 320-370 J/g and long-term storage stability (half-life of about 3 months). On this basis, we fabricate high-performance, flexible film devices of solar thermal battery, which can be readily recharged at room temperature with good cycling ability, show fast rate of heat release, and produce high-temperature heat that is >20<sup> o</sup>C higher than the ambient temperature. Our work opens up a new avenue to harvest ambient heat, and demonstrate a feasible strategy to develop high-performance solar thermal battery.

Sign in / Sign up

Export Citation Format

Share Document