Implementation of continuous fast scanning detection in femtosecond Fourier-transform two-dimensional vibrational-electronic spectroscopy to decrease data acquisition time

2018 ◽  
Vol 89 (11) ◽  
pp. 113104 ◽  
Author(s):  
Zachary W. Fox ◽  
Tyler J. Blair ◽  
Robert B. Weakly ◽  
Trevor L. Courtney ◽  
Munira Khalil
Keyword(s):  
Fourier Transform ◽  
Data Acquisition ◽  
Electronic Spectroscopy ◽  
Acquisition Time ◽  
Two Dimensional ◽  
Data Acquisition Time ◽  
Scanning Detection

scholarly journals Two-color two-dimensional Fourier transform electronic spectroscopy with a pulse-shaper

2008 ◽  
Vol 16 (22) ◽  
pp. 17420 ◽  
Author(s):  
Jeffrey A. Myers ◽  
Kristin L. Lewis ◽  
Patrick F. Tekavec ◽  
Jennifer P. Ogilvie
Keyword(s):  
Fourier Transform ◽  
Electronic Spectroscopy ◽  
Two Dimensional ◽  
Pulse Shaper

scholarly journals TEM Random & Ultra-fast Precession ED Tomography for analysis of nm crystals

2014 ◽  
Vol 70 (a1) ◽  
pp. C371-C371 ◽  
Author(s):  
Stavros Nicolopoulos ◽  
Mauro Gemmi ◽  
Alexander Eggeman ◽  
Paul Midgley ◽  
Athanassios Galanis
Keyword(s):  
Electron Microscopy ◽  
Electron Diffraction ◽  
Data Acquisition ◽  
Automatic Measurement ◽  
Ccd Camera ◽  
Acquisition Time ◽  
Diffraction Tomography ◽  
Organic Pigments ◽  
Precession Electron Diffraction ◽  
Data Acquisition Time

Since the invention of Precession Electron Diffraction (PED) in Transmission Electron Microscopy (TEM) by Vincent & Midgley [1] in 1994 and mainly after the introduction of dedicated PED devices to different TEM, the structure of various nano-sized crystals have been solved by Electron Crystalography. The most popular technique that was recently developed based on beam precession is the 3D Precession Diffraction Tomography (PEDT) [2]. A series of ED patterns are collected every 10while the sample is tilted around the goniometer axis. By the automatic measurement of ED intensities (ADT 3D software), the unit cell, crystal symmetry and the detailed crystal structure can be determined. A large number of crystal structures, such as complex metals, alloys, organic pigments, MOF, catalysts etc., have been solved by the 3D PEDT technique. A drawback of 3D PEDT (especially for beam sensitive materials) is the long acquisition times (45–120 min), due to the time consuming step of tracking the crystal under the beam during tilting. To deal with this problem, we have developed two novel approaches: the Random Electron Diffraction Tomography (rPEDT) technique and the Ultra-Fast 3D diffraction tomography (UF PEDT) [3]. By rPEDT technique, a sample area (few microns), where several crystals in different (random) orientations are present, is scanned rapidly using an ASTAR precession device (NanoMEGAS SPRL). PED patterns of all scanned crystals are collected by a fast speed CCD camera (up to 120 frames/sec; 8/12 bit). Concerning UF PEDT, the data acquisition time can be 10-20 times faster compared to hitherto 3D PEDT procedure. UF PEDT can be applied when the crystal shift is stable and reproducible during tilting the sample for a specific tilt range. Thus, such crystals can be tracked by shifting the beam following the crystal displacement during tilting (using ASTAR beam scanning). Obtained PED patterns can be recorded with a fast CCD camera, while crystal is tilted. As a conclusion, rPEDT and UF-PEDT can be considered as breakthrough techniques in electron crystallography as they can be performed in any commercial TEM. Both techniques reduce considerable 3D intensity data acquisition time, and allow the analysis of unknown compounds, including beam sensitive organic crystals, as fast techniques prevents crystal beam damage. The authors acknowledge financial support from EU ESTEEM-2 project (European Network for Electron Microscopy www.esteem2.eu).

scholarly journals Data acquisition time minimization in FANET-based IoT networks

2021 ◽  
Vol 49 (1) ◽  
Author(s):  
Alaa Taima Albu-Salih ◽  
◽  
Osama Majeed Hilal ◽  
Hayder Ayad Khudhair ◽  
◽  
...  
Keyword(s):  
Data Acquisition ◽  
Optimization Model ◽  
Ad Hoc Network ◽  
Ad Hoc ◽  
Data Gathering ◽  
Acquisition Time ◽  
Iot Applications ◽  
Time Minimization ◽  
Efficient Data ◽  
Data Acquisition Time

Unmanned aerial vehicles (UAVs) is widely used in many military, and civilian applications. UAVs communicate in a Flying Ad hoc Network (FANET) environment where UAVs communicate with each other through an ad hoc network without infrastructure. FANET provide a flexible platform for internet of things (IoT) applications by playing different roles in IoT such as mobile data collector. In fact, in deadline based IoT applications, the deadline is restricted to the critical application level. And as a result, this deadline for data acquisition is not adequate, and FANET cannot collect data from the sensed area with the predetermined deadline. In this paper, a novel efficient data gathering approach for IoT using FANET is proposed. The main objective of this approach is to solve the problem of insufficient deadlines given by FANET in IoT-based deadline applications. Authors will first provide a multi-objective optimization model as a MILP optimization model to solve this problem, and then normalize and add two weighing coefficients to solve the MILP model. The results obtained in the simulation show that the proposed approach can provide efficient data acquisition while guaranteeing the deadline time.

Two-quantum Two-dimensional Fourier Transform Electronic Spectroscopy of Biexcitons in GaAs Quantum Wells

2009 ◽  
pp. 250-252
Author(s):  
Katherine W. Stone ◽  
Kenan Gundogdu ◽  
Daniel B. Turner ◽  
Xiaoqin Li ◽  
Steven T. Cundiff ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Quantum Wells ◽  
Electronic Spectroscopy ◽  
Two Dimensional
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