A case study of using Raman lidar measurements in high-accuracy GPS applications

2009 ◽  
Vol 84 (4) ◽  
pp. 251-265 ◽  
Author(s):  
Pierre Bosser ◽  
Olivier Bock ◽  
Christian Thom ◽  
Jacques Pelon ◽  
Pascal Willis
Keyword(s):  
High Accuracy ◽  
Raman Lidar ◽  
Lidar Measurements

Case study of Raman lidar measurements of Asian dust events in 2000 and 2001 at Nagoya and Tsukuba, Japan

2002 ◽  
Vol 36 (35) ◽  
pp. 5479-5489 ◽  
Author(s):  
Tetsu Sakai ◽  
Takashi Shibata ◽  
Yasunobu Iwasaka ◽  
Tomohiro Nagai ◽  
Masahisa Nakazato ◽  
...  
Keyword(s):  
Asian Dust ◽  
Raman Lidar ◽  
Lidar Measurements ◽  
Dust Events

Convection initiation and bore formation following the collision of mesoscale boundaries over a developing stable boundary layer: a case study from PECAN

2021 ◽  
Author(s):  
Guo Lin ◽  
Coltin Grasmick ◽  
Bart Geerts ◽  
Zhien Wang ◽  
Min Deng
Keyword(s):  
Great Plains ◽  
Deep Convection ◽  
Density Currents ◽  
Raman Lidar ◽  
Frontal Surface ◽  
Thermodynamic Structure ◽  
Lidar Measurements ◽  
Outflow Boundary ◽  
Convection Initiation

AbstractThis observational study documents the consequences of a collision between two converging shallow atmospheric boundaries over the central Great Plains on the evening of 7 June 2015. This study uses data from a profiling airborne Raman lidar (the Compact Raman Lidar, or CRL) and other airborne and ground-based data collected during the Plains Elevated Convection At Night (PECAN) field campaign to investigate the collision between a weak cold front and the outflow from a MCS. The collision between these boundaries led to the lofting of high-CAPE, low-CIN air, resulting in deep convection, as well as an undular bore. Both boundaries behaved as density currents prior to collision. Because the MCS outflow boundary was denser and less deep than the cold-frontal airmass, the bore propagated over the latter. This bore was tracked by the CRL for about three hours as it traveled north over the shallow cold-frontal surface and evolved into a soliton. This case study is unique by using the high temporal and spatial resolution of airborne Raman lidar measurements to describe the thermodynamic structure of interacting boundaries and a resulting bore.

A case study on the vertical distribution and characteristics of aerosols using ground-based raman lidar, satellite and model over Western India

2021 ◽  
Vol 42 (17) ◽  
pp. 6421-6436
Author(s):  
Sourita Saha ◽  
Som Sharma ◽  
K. Niranjan Kumar ◽  
Prashant Kumar ◽  
Vaidehi Joshi ◽  
...  
Keyword(s):  
Vertical Distribution ◽  
Western India ◽  
Raman Lidar ◽  
The Vertical Distribution

scholarly journals EARLINET dust observations vs. BSC-DREAM8b modeled profiles: 12-year-long systematic comparison at Potenza, Italy

2014 ◽  
Vol 14 (16) ◽  
pp. 8781-8793 ◽  
Author(s):  
L. Mona ◽  
N. Papagiannopoulos ◽  
S. Basart ◽  
J. Baldasano ◽  
I. Binietoglou ◽  
...  
Keyword(s):  
Center Of Mass ◽  
Saharan Dust ◽  
Raman Lidar ◽  
Dust Layer ◽  
Systematic Comparison ◽  
Dust Extinction ◽  
Lidar Measurements ◽  
Order Of Magnitude ◽  
Lidar Ratio ◽  
532 Nm

Abstract. In this paper, we report the first systematic comparison of 12-year modeled dust extinction profiles vs. Raman lidar measurements. We use the BSC-DREAM8b model, one of the most widely used dust regional models in the Mediterranean, and Potenza EARLINET lidar profiles for Saharan dust cases, the largest one-site database of dust extinction profiles. A total of 310 dust cases were compared for the May 2000–July 2012 period. The model reconstructs the measured layers well: profiles are correlated within 5% of significance for 60% of the cases and the dust layer center of mass as measured by lidar and modeled by BSC-DREAM8b differ on average 0.3 ± 1.0 km. Events with a dust optical depth lower than 0.1 account for 70% of uncorrelated profiles. Although there is good agreement in terms of profile shape and the order of magnitude of extinction values, the model overestimates the occurrence of dust layer top above 10 km. Comparison with extinction profiles measured by the Raman lidar shows that BSC-DREAM8b typically underestimates the dust extinction coefficient, in particular below 3 km. Lowest model–observation differences (below 17%) correspond to a lidar ratio at 532 nm and Ångström exponent at 355/532 nm of 60 ± 13 and 0.1 ± 0.6 sr, respectively. These are in agreement with values typically observed and modeled for pure desert dust. However, the highest differences (higher than 85%) are typically related to greater Ångström values (0.5 ± 0.6), denoting smaller particles. All these aspects indicate that the level of agreement decreases with an increase in mixing/modification processes.

scholarly journals Tropospheric water vapour and relative humidity profiles from lidar and microwave radiometry

2014 ◽  
Vol 7 (5) ◽  
pp. 1201-1211 ◽  
Author(s):  
F. Navas-Guzmán ◽  
J. Fernández-Gálvez ◽  
M. J. Granados-Muñoz ◽  
J. L. Guerrero-Rascado ◽  
J. A. Bravo-Aranda ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Water Vapour ◽  
Microwave Radiometer ◽  
Radiosonde Data ◽  
Mixing Ratio ◽  
Raman Lidar ◽  
Night Time ◽  
New Approach ◽  
Lidar Measurements ◽  
Humidity Profiles

Abstract. In this paper, we outline an iterative method to calibrate the water vapour mixing ratio profiles retrieved from Raman lidar measurements. Simultaneous and co-located radiosonde data are used for this purpose and the calibration results obtained during a radiosonde campaign in summer and autumn 2011 are presented. The water vapour profiles measured during night-time by the Raman lidar and radiosondes are compared and the differences between the methodologies are discussed. Then, a new approach to obtain relative humidity profiles by combination of simultaneous profiles of temperature (retrieved from a microwave radiometer) and water vapour mixing ratio (from a Raman lidar) is addressed. In the last part of this work, a statistical analysis of water vapour mixing ratio and relative humidity profiles obtained during 1 year of simultaneous measurements is presented.

Raman lidar measurements of Pinatubo aerosols over southeastern Kansas during November-December 1991

1992 ◽  
Vol 19 (15) ◽  
pp. 1599-1602 ◽  
Author(s):  
R. A. Ferrare ◽  
S. H. Melfi ◽  
D. N. Whiteman ◽  
K. D. Evans
Keyword(s):  
Raman Lidar ◽  
Lidar Measurements

scholarly journals A design methodology for approximate multipliers in convolutional neural networks: A case of MNIST

2021 ◽  
Vol 10 (1) ◽  
pp. 1
Author(s):  
Kenta Shirane ◽  
Takahiro Yamamoto ◽  
Hiroyuki Tomiyama
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Convolutional Neural Network ◽  
Design Methodology ◽  
Critical Path ◽  
High Accuracy ◽  
Path Delay ◽  
Trade Off ◽  
Critical Path Delay

In this paper, we present a case study on approximate multipliers for MNIST Convolutional Neural Network (CNN). We apply approximate multipliers with different bit-width to the convolution layer in MNIST CNN, evaluate the accuracy of MNIST classification, and analyze the trade-off between approximate multiplier’s area, critical path delay and the accuracy. Based on the results of the evaluation and analysis, we propose a design methodology for approximate multipliers. The approximate multipliers consist of some partial products, which are carefully selected according to the CNN input. With this methodology, we further reduce the area and the delay of the multipliers with keeping high accuracy of the MNIST classification.

scholarly journals Developing an Analytical Solution that Mimics Simulation Modeling for Construction Planning: Earthwork Case

2019 ◽  
pp. 552-562
Author(s):  
Waleed Shakeel ◽  
Ming Lu
Keyword(s):  
Analytical Solution ◽  
Dynamic System ◽  
Simulation Modeling ◽  
High Accuracy ◽  
Analytical Tool ◽  
Controlled Experiments ◽  
Cost Estimating ◽  
Construction Planning ◽  
Using Data

Deriving a reliable earthwork job cost estimate entails analysis of the interaction of numerous variables defined in a highly complex and dynamic system. Using simulation to plan earthwork haul jobs delivers high accuracy in cost estimating. However, given practical limitations of time and expertise, simulation remains prohibitively expensive and rarely applied in the construction field. The development of a pragmatic tool for field applications that would mimic simulation-derived results while consuming less time was thus warranted. In this research, a spreadsheet based analytical tool was developed using data from industry benchmark databases (such as CAT Handbook and RSMeans). Based on a case study, the proposed methodology outperformed commonly used estimating methods and compared closely to the results obtained from simulation in controlled experiments.

Prediction and Analysis of Safety Production Accident in Mining Based on the GM(1,1)

2014 ◽  
Vol 989-994 ◽  
pp. 3443-3446
Author(s):  
Chen Fang Jiang ◽  
Ke Peng Hou ◽  
Hua Fen Sun
Keyword(s):  
Production Management ◽  
Management Practices ◽  
Safety Management ◽  
High Accuracy ◽  
Mine Safety ◽  
Grey Theory ◽  
Procedure Code ◽  
Safety Production ◽  
Mine Accidents

According to the grey theory, in order to predict and prevent accident effectively, the paper built a grey model and forecast the mine accidents in china in 2013 based on the statistics of mine accidents happened in China during period from 2007 to 2012. MATLAB was used to write procedure code of GM (1, 1) and empirical verification follows. The prediction results show that if high accuracy goes with the precision of the calculable model, which could be used to provide the basis for decision making to the safety production management practices in China. This case study indicates that GM (1, 1) plays an important role in mine safety management.

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