2,832 research outputs found
Measurement of Planetary Boundary Layer Winds with Scanning Doppler Lidar
The accurate measurement of wind profiles in the planetary boundary layer (PBL) is important not only for numerical weather prediction, but also for air quality modeling. Two wind retrieval methods using scanning Doppler light detection and ranging (lidar) measurements were compared and validated with simultaneous radiosonde soundings. A comparison with 17 radiosonde sounding profiles showed that the sine-fitting method was able to retrieve a larger number of data points, but the singular value decomposition method showed significantly smaller bias (0.57 m s(-1)) and root-mean-square error (1.75 m s(-1)) with radiosonde soundings. Increasing the averaging time interval of radial velocity for obtaining velocity azimuth display scans to 15 min resulted in better agreement with radiosonde soundings due to the signal averaging effect on noise. Simultaneous measurements from collocated wind Doppler lidar and aerosol Mie-scattering lidar revealed the temporal evolution of PBL winds and the vertical distribution of aerosols within the PBL
Implementing the Duty Trip Support Application
We are in the process of developing an agent and ontology-based Duty Trip Support application. The goal of this paper is to consider issues arising when implementing such a system. In addition to the description of our current implementation, which is also critically analyzed, other possible approaches are considered as well.software agents, agent systems, ontologies, transport objects, agent-non-agent integration.
Proto-type installation of a double-station system for the optical-video-detection and orbital characterisation of a meteor/fireball in South Korea
We give a detailed description of the installation and operation of a
double-station meteor detection system which formed part of a research &
education project between Korea Astronomy Space Science Institute and Daejeon
Science Highschool. A total of six light-sensitive CCD cameras were installed
with three cameras at SOAO and three cameras at BOAO observatory. A
double-station observation of a meteor event enables the determination of the
three-dimensional orbit in space. This project was initiated in response to the
Jinju fireball event in March 2014. The cameras were installed in
October/November 2014. The two stations are identical in hardware as well as
software. Each station employes sensitive Watec-902H2 cameras in combination
with relatively fast f/1.2 lenses. Various fields of views were used for
measuring differences in detection rates of meteor events. We employed the
SonotaCo UFO software suite for meteor detection and their subsequent analysis.
The system setup as well as installation/operation experience is described and
first results are presented. We also give a brief overview of historic as well
as recent meteor (fall) detections in South Korea. For more information please
consult http://meteor.kasi.re.kr .Comment: Technical/instrumentation description of a professional meteor
detection system, 23 pages, 20 figures (color/monochrome), 5 tables,
submitted to the Journal of Korean Astronomical Society (JKAS,
http://jkas.kas.org/, http://jkas.kas.org/history.html
Rapid quantification of DNA methylation through dNMP analysis following bisulfite-PCR
We report a novel method for rapid quantification of the degree of DNA methylation of a specific gene. Our method combined bisulfite-mediated PCR and quantification of deoxyribonucleoside monophosphate (dNMP) contents in the PCR product through capillary electrophoresis. A specific bisulfite-PCR product was enzymatically hydrolyzed to dNMP monomers which were quantitatively analyzed through subsequent capillary electrophoresis. PCR following bisulfite treatment converts unmethylated cytosines to thymines while leaving methyl-cytosines unchanged. Then the ratio of cytosine to thymine determined by capillary electrophoresis represents the ratio of methyl-cytosine to cytosine in genomic locus of interest. Pure oligonucleotides with known sequences were processed in parallel as standards for normalization of dNMP peaks in capillary electrophoresis. Sources of quantification uncertainty such as carryovers of dNTPs or primers and incomplete hydrolysis were examined and ruled out. When the method was applied to samples with known methylation levels (by bisulfite-mediated sequencing) as a validation, deviations were within ±5%. After bisulfite-PCR, the analytical procedure can be completed within 1.5 h
Spatio-Temporal Variability of Aerosol Optical Depth, Total Ozone and NO(2)Over East Asia: Strategy for the Validation to the GEMS Scientific Products
In this study, the spatio-temporal variability of aerosol optical depth (AOD), total column ozone (TCO), and total column NO2(TCN) was identified over East Asia using long-term datasets from ground-based and satellite observations. Based on the statistical results, optimized spatio-temporal ranges for the validation study were determined with respect to the target materials. To determine both spatial and temporal ranges for the validation study, we confirmed that the observed datasets can be statistically considered as the same quantity within the ranges. Based on the thresholds of R-2>0.95 (temporal) and R>0.95 (spatial), the basic ranges for spatial and temporal scales for AOD validation was within 30 km and 30 min, respectively. Furthermore, the spatial scales for AOD validation showed seasonal variation, which expanded the range to 40 km in summer and autumn. Because of the seasonal change of latitudinal gradient of the TCO, the seasonal variation of the north-south range is a considerable point. For the TCO validation, the north-south range is varied from 0.87 degrees in spring to 1.05 degrees in summer. The spatio-temporal range for TCN validation was 20 min (temporal) and 20-50 km (spatial). However, the nearest value of satellite data was used in the validation because the spatio-temporal variation of TCN is large in summer and autumn. Estimation of the spatio-temporal variability for respective pollutants may contribute to improving the validation of satellite products
Automatic 3D Registration of Dental CBCT and Face Scan Data using 2D Projection images
This paper presents a fully automatic registration method of dental cone-beam
computed tomography (CBCT) and face scan data. It can be used for a digital
platform of 3D jaw-teeth-face models in a variety of applications, including 3D
digital treatment planning and orthognathic surgery. Difficulties in accurately
merging facial scans and CBCT images are due to the different image acquisition
methods and limited area of correspondence between the two facial surfaces. In
addition, it is difficult to use machine learning techniques because they use
face-related 3D medical data with radiation exposure, which are difficult to
obtain for training. The proposed method addresses these problems by reusing an
existing machine-learning-based 2D landmark detection algorithm in an
open-source library and developing a novel mathematical algorithm that
identifies paired 3D landmarks from knowledge of the corresponding 2D
landmarks. A main contribution of this study is that the proposed method does
not require annotated training data of facial landmarks because it uses a
pre-trained facial landmark detection algorithm that is known to be robust and
generalized to various 2D face image models. Note that this reduces a 3D
landmark detection problem to a 2D problem of identifying the corresponding
landmarks on two 2D projection images generated from two different projection
angles. Here, the 3D landmarks for registration were selected from the
sub-surfaces with the least geometric change under the CBCT and face scan
environments. For the final fine-tuning of the registration, the Iterative
Closest Point method was applied, which utilizes geometrical information around
the 3D landmarks. The experimental results show that the proposed method
achieved an averaged surface distance error of 0.74 mm for three pairs of CBCT
and face scan datasets.Comment: 8 pages, 6 figures, 2 table
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